Guide to defeating Magni the Bison

Magni the Bison
Magni the Bison is a level 24 warrior boss, with all that being a boss entails: very high health (killing him requires dealing around 1300 HP to him), double damage, +3 health regeneration, and half skill activation time. If you don't have any defensive skills but try to trade hits, you'll probably die within ten seconds. As such, any strategy to beat the tournament must start with a way to beat him. There are at least five basic approaches that can usually work:


 * Keep him blinded so he rarely hits you.
 * Keep him crippled and kill him from a distance.
 * Keep him weakened to limit damage and bring copious healing.
 * Bring a myriad of blocking skills to block most of his attacks.
 * Keep Protective Spirit on yourself to limit his damage.

Bison has two knockdown skills, so even some skills will be interrupted if he hits you. He also has a third skill which will knock you down if you block it, so blocking skills don't reduce his knockdowns by much. This means that relatively few builds can invariably beat him, though many can beat him most of the time, so long as you aren't interrupted by one of his knockdowns at a particularly inopportune time.

Furthermore, Bison has Purge Signet which will remove all hexes and conditions from him. He won't use it just to remove crippled or bleeding, but will use it as often as the cooldown allows to remove blindness, weakness, burning, dazed, and/or poison. As such, if you're relying on kiting, it may be best to avoid using conditions other than crippled and bleeding, so that he doesn't use Purge Signet and thereby remove crippled.

As he is a warrior, if you use a martial weapon, switching to one that does elemental damage can make the battle go faster. This is rarely the difference between winning and losing, but it can substantially shorten the time it takes to defeat him.

Assembling a build
As you must beat five other opponents in order to reach Bison, any build that can beat him but not the preceding opponents is useless. As such, your build will need to be well-rounded.

Keep in mind that skills whose value lies in the fact that they affect multiple opponents or multiple allies tend to be less useful here, as there is usually only one opponent and only one ally (namely, you). Conversely, skills typically limited by the fact that they only affect one opponent can be highly useful.

The polar opposite of Bison's massive damage with no healing approach is the opponents who have little interest in killing you, but will spam self-heals to try for a stalemate. You'll have to bring skills to either cause a substantial damage spike of 200+ HP within several seconds, or else bring interrupts or some other way to stop their healing.

It is also vital that you bring self-healing skills. Many mobs cannot be finished off before they'll do enough damage to kill you if you can't heal yourself. For several opponents, it is necessary to wait until they are low on energy before you can do much damage, and you'll have to spend a lot of time healing before that.

Health degeneration hexes and conditions are useful, as, unlike a lot of PvE combat where, when you put a 20 second condition on a mob and it dies 5 seconds later, you often get the full duration of health degeneration on the opponent--and if you don't, it usually means you won.

Opponents with interrupts can reliably interrupt skills with an activation time of 1 or more seconds if you don't have a way to prevent them from doing so. Skills with a 3/4 second activation time are only infrequently interrupted. Skills that activate faster than that are pretty safe to cast, and generally interrupted only by dumb luck when an opponent knocks you down without trying to interrupt anything in particular. If you need to get a longer cast off, choose your timing wisely.

A simple trick to increase your maximum health at least a little, is to activate your Norn Title. Even a rank of 1 will provide you with an additional 53 HP.

Earlier tournament opponents
Some opponents are pretty easy to beat with any reasonable build. Here are some tips against the ones that can be hard.

Danika, Sheena, and Brutus
You have to fight all three at once. Danika does virtually no damage, but spams heals on the others. Sheena and Brutus do some damage, but are only level 10. Killing Danika first is probably impractical, but once Sheena and Brutus are dead, finishing off Danika is just a matter of time. Killing Brutus and/or Sheena does not end the match; you have to beat Danika, too.

Zho and Onyx
You fight both at once. Killing Zho wins the match, while killing Onyx doesn't matter. They don't hit very hard, but Onyx will interrupt/disable skills. Focus on Zho, and avoid using vital skills when Onyx activates Disrupting Lunge.

Old Mac and Joe
You fight both at once and killing either one wins the match. If you're playing as a caster, it's often vital that you find a way to avoid Broad Head Arrow (used by Joe).

Kisai, Headmaster Vhang, and Argo
These are three separate fights, but similar in style. Killing them immediately will be impractical for some classes. Focus on keeping yourself alive until they run out of energy, at which point they'll stop casting anything with an energy cost above 5. That reduces them to casting some weak attacks and no defensive spells, at which point it is easy to defeat them.

Eve and Norgu
These are two separate fights, but similar in style. Both will cast some hexes on you that can be pretty nasty depending on your build. They run out of energy after a while, and their casting slows considerably. You may only be able to attack or cast spells intermittently because their damage is produced primarily by hexes like Spiteful Spirit. Sometimes you'll want to finish off an opponent by attacking through Empathy or Spiteful Spirit and just taking the damage. Be careful when using spells with long cast times when fighting Eve since her interrupt skills also restore her energy.

Mhenlo
Mhenlo is a 55 Monk, so he'll only take 5 damage from normal attacks. He has a permanent Protective Spirit, so you can't just wait for it to wear off. Additionally, he uses skills which provide health regeneration, attempting to beat him via damage alone (at 5 damage per attack) is impractical. However, because his healing is produced by health regeneration, Mhenlo gets destroyed by health degeneration, lifestealing, and/or enchantment removal, so he's very easy if you have any of those. Energy denial to prevent his healing, or repeatedly interrupting Healing Breeze works too, provided that he doesn't cast Mending. It may take a while to interrupt enough of his vital skills successively, so you'll need to be able to interrupt him on demand.

Razah
Razah is a Spirit Spammer who won't move far from its spawn point, so you can't just lure it away from its spirits. Shadowsong and Wanderlust are its nastiest spirits, and can make killing it very difficult if you sit back and let it cast its spirits. An area of effect attack to kill all of the spirits can be very effective. Some builds are able to simply ignore the spirits and kill Razah before it can get very many of them up.

Melonni
Killing Melonni while she has Avatar of Dwayna up is often impractical, as it provides considerable healing and hex removal. Keep yourself alive until it wears off and then she's easy to kill.

Lukas
Lukas is purely anti-melee and thus quite easy for any non-melee class to defeat. His Riposte, Deadly Riposte, and Auspicious Parry will block many melee skills however, and can cause a lot of damage as well. Melee classes will have to strike an effective balance between attacking him and healing themselves.

Alesia
Alesia doesn't deal very much damage, but her use of Mending, Healing Breeze, and Healing Hands may force a stalemate, as she has at least 13 points in Healing Prayers. Energy denial and interrupts (especially from dazed) help greatly, though dragging out the fight until she loses her energy and then killing her will also work.

Devona
Devona brings three self-heals, so outdamaging her healing over the long run may be impractical. She won't use them until she gets to about half life, though, so you can try to finish her off by spiking her quickly and/or interrupting a couple heals. She also brings two knockdowns, which can interfere with your attempts at producing a spike, so it sometimes takes a number of tries to finish her off.

Warmaster Tydus
Tydus brings massive health degeneration and can interrupt your attempts at healing yourself. His only healing skill is Troll Unguent however, so if you can interrupt that, he dies pretty quickly.

Ghostly Hero
The Ghostly Hero is level 28, which turns out to not be terribly consequential. He'll use a bow at a distance and a sword in melee range, much like the Doppelganger. His immunity to bleeding can mess up some builds, but that's the only thing that can make him much of a challenge.

Single class builds
Often when people ask how to beat the tournament, they get a reply of, take a different secondary profession and buy or capture a bunch of skills for it. That can be perfectly sensible if you wish to farm the tournament and get dozens of Bison Championship Tokens, but it is probably impractical if you only want to beat it once.

Any class is capable of beating the tournament using only skills from its primary profession. The purpose of this section is to provide builds that use skills from only one class, so they are skills that you likely already have, and should probably consider getting if you don't.

If you don't have all of the campaigns, that may make some of the skills in the builds listed unavailable to you. Some skills are easily swapped out for others (e.g., if you don't have Prophecies, replace Disciplined Stance with some other blocking stance) while others are essential to the build (e.g., the Mesmer requires Signet of Midnight).

Many of the builds listed here have been tested and they are all capable of defeating Bison if used properly. In most cases, gear isn't terribly important, provided that it's reasonable. Obviously, you want max armor, max damage weapons, perfect or near-perfect mods that are sensible for your build, and useful insignias and runes in all slots. Although not necessary, bringing several kinds of weapons (e.g. elemental, physical, vampiric, etc.) will shorten the fights. Cases in which gear does matter are expressly pointed out.

Minor Runes are generally more useful here, since you're dueling and the participant with higher maximum health may win by default. If you decide to go with Major or Superior Runes, be sure to have sufficient defense to counter the health loss.

Warrior

 * 12 Swordsmanship
 * 12 Tactics
 * 11 Strength

This build requires use of a sword.

The idea is to block most of Bison's attacks. One of the three stances should be kept up at most times. As each particular stance can only be up a minority of the time, take care not to end a stance until it was about to end on its own, anyway. Use Riposte, Deadly Riposte, and Lion's Comfort as often as available, and Bonetti's Defense rather than one of the energy-using stances as often as it is available, to recharge your energy. You do damage mainly with Riposte and Deadly Riposte, and while this build can't keep you alive forever, it can outlast Bison. Using Healing Signet against Bison takes a large risk of him hitting you and finishing you off during the cast.

Some of the enemies like to spam heals and take quite a while to wear down, but it can eventually finish off opponents like Mhenlo or Danika. From unattempted opponents, only Eve may be a hindrance for this build.

Opponents not attempted: Eve, Devona

Ranger

 * 11 Marksmanship
 * 11 Wilderness Survival
 * 13 Expertise

The approach here is to keep Bison perpetually crippled, so that you can avoid getting hit. If you avoid using poison and burning, Bison won't use purge signet, which makes him easier to kite, though these will finish him off faster. Baiting Purge Signet is easy, and if your reflexes are good, it can be interrupted. If you run around some, Bison often runs back to his spawn point while crippled before coming back to attack you, so kiting is practical. Bleeding from Hunter's Shot will negate his natural regeneration while you slowly wear him down.

Danika cannot be defeated, at least not easily, using this build. Most other opponents should go down quite quickly. For casters with a lot of defense like Argo, you will need to wait for their energy to run out. Casters using blind will exhaust their energy fairly quickly, and won't be able to outdamage Troll Unguent. The Ghostly Hero is immune to poison and bleeding, and will outdamage you easily if you forget to use Whirling Defense. Otherwise, he is easy to take down.

Nature's Renewal is a critical part of the build, as it really messes with the AI if you drop it behind the wall before entering the arena. The only reason this build can beat Tydus is that instead of attacking you, he mostly stands there and shoots the wall, trying to kill the spirit. Some enemies won't even bother trying to cast potentially nasty hexes, and those that do are much easier to interrupt with the doubled casting time. Gwen in particular doesn't use any skills, but just stands there wanding.

Opponents not attempted: Palawa Joko (Most likely immune to poison and bleeding)

Monk

 * 13 Protection Prayers
 * 11 Smiting Prayers
 * 11 Divine Favor

Keep Protective Spirit and Retribution up at all times against Bison, and Defender's Zeal on him as much of the time as possible. Protective spirit ensures that he can't knock too much life off of you. Reversal of Fortune is your main healing spell, and you'll have to use it every several seconds. Retribution and Reversal of Damage are how you do the damage to kill Bison. Defender's Zeal and Castigation Signet are for energy management, and the latter should be used as often as possible.

This build cannot beat Razah or Devona, but can beat almost everyone else. Of the opponents haven't faced, it would likely struggle with Danika and Mhenlo. Opponents that rely heavily on degeneration are typically difficult, but beatable. Those that like to start healing at about half life can usually be finished off with Bane Signet, Holy Strike, and Castigation Signet in that order, starting just above the threshold at which the character heals, and while the character is attacking so that bane signet will knock him down. This doesn't work with Devona because her lifeline is just too long.

Opponents not attempted: Alesia, Melonni, Danika, Ghostly Hero, Mhenlo

Necromancer

 * 14 Blood Magic
 * 13 Curses

Sorry to use a PvE-only skill here, but without a decent direct damage skill, it simply wasn't possible to do adequate damage against some opponents. Having a reasonably high Sunspear rank (approximately rank 8) is only necessary against a couple opponents like Devona and Alesia that play for the stalemate, not the win.

You're going to get hit a lot, so you must keep Bison weakened at all times, and you'll still need massive healing. Enfeeble and Enfeebling Touch are both necessary to ensure that one is always available, as otherwise, Bison could get a few hits off right after purging weakness. Use blood renewal as often as available, and Grenth's Balance right after blood renewal, to fully heal yourself after the substantial sacrifice. Use parasitic bond for additional healing as energy allows. You mainly damage Bison with Grenth's Balance.

Of those opponents not faced, only Old Mac and Danika look potentially troublesome.

Opponents not attempted: Melonni, Old Mac, Danika, Panaku, Kahmu, Nika

Mesmer

 * 14 Domination Magic
 * 12 Inspiration Magic
 * 7 Fast Casting

Keep Ignorance on Bison at all times, so that he can't purge blindness. Remember to keep him perpetually blinded with Signet of Midnight. Spirit of Failure is great energy management, as at 12 inspiration magic, it's +3 energy every time he misses, which is 92.5% of the time. Empathy is how you do damage, and use Ether Feast to heal as needed.

The only opponent that was faced and not beaten was Danika, though she may be beatable with alternate tactics. Razah is difficult, but beatable. This build handily destroys every other opponent. Potentially annoying enemy healing is blocked with either Spirit Shackles or Ignorance, depending on the opponent. Of those not fought, Gwen may prove to be a trouble.

Opponents not attempted: Koss, Gwen, Mhenlo, Nika

Elementalist

 * 14 Air Magic
 * 11 Energy Storage
 * 9 Earth Magic

The idea is to spam Blinding Surge on Bison to keep him blinded most of the time. Kinetic Armor reduces the damage you take when hit, and should be easy to cast once and keep up for the rest of the battle after that. Aura of Restoration can outheal the damage that Bison does when he occasionally lands a hit. Air Attunement and Glyph of Lesser Energy are for energy management, and should be used as often as possible.

This build should be able to overcome all opponents, even those that haven't been tried. Mhenlo takes long enough that if you draw him as an opponent, it may be quicker to just give up. Beating Mhenlo requires interrupting two consecutive casts of Healing Breeze, which can take many tries, as you must start casting Gale before he starts casting Healing Breeze in order to interrupt it.

Opponents not attempted: Orion, Danika, Razah, Nika

Assassin

 * 12 Shadow Arts
 * 12 Dagger Mastery
 * 11 Critical Strikes

Start the fight by using Smoke Powder Defense. When Bison first hits you, he'll be blinded, and immediately purge it. Be ready with Temple Strike immediately after he purges his blindness. Wait until right about when that wears off to hit him with blinding powder. If you wait long enough, he'll waste Purge Signet removing blindness right as it is about to wear off, at which point you hit him with Temple Strike again and repeat the process. If you wait too long, you'll have to use Smoke Powder Defense to re-blind him in order to get him to waste Purge Signet. Shadow refuge is your healing skill. Jagged Strike is recommended for its very quick recharge, low energy cost, and ability to do massive damage from bleeding since you can only use it infrequently due to energy constraints and the large energy cost of Temple Strike.

Most of the opponents can be beaten with this build, but Lukas can be a challenge. Time your Disrupting Stab correctly to interrupt his Healing Signet. Among opponents that were not faced, only Eve looks like a potential problem.

Opponents not attempted: Kilroy, Old Mac, Eve, Devona

Ritualist

 * 13 Channeling
 * 11 Communing
 * 11 Spawning Power

Start by casting Ritual Lord and Boon of Creation before the battle starts, so that if something goes wrong, you can recast spirits later. Stand in the doorway before entering the arena and cast the four spirits in order. You should position yourself such that when the door closes, the spirits will be inside of it--and not behind it, or it will block their attacks. Cast Painful Bond on your opponent when he comes over, and the spirits will promptly destroy him. Against Bison, wait for him to use Purge Signet once before casting Painful Bond so he doesn't immediately remove it. When you enter the arena, it's a good idea to run sideways a bit to put some space between you and the spirits. Several of your opponents may open with an AoE attack which will quickly destroy the stationary spirits.

Vampirism can replace one of the spirits if you have high Sunspear rank, or if you're missing one of the binding ritual skills. In case you find placing spirits inside the door difficult, you can bring Summon Spirits to pull the spirits through the door (you must cast after you cross the threshold but before the gate fully closes or they will remain outside).

Mhenlo, Norgu, and Razah have funky AI, so the battle proceeds a little differently, but they're quite beatable. Argo will destroy the spirits while taking minimal damage, making for a harder fight. Most opponents should be easy unless they have unusual AI, causing them to not die in the normal manner.

Opponents not attempted: Sogolon, Old Mac

Dervish

 * 12 Mysticism
 * 12 Scythe Mastery
 * 11 Earth Prayers

It is absolutely essential to use an ebon scythe. If you don't have one, you can try to compensate with Dust Cloak or Staggering Force, however both skills cost 10e which would make energy management difficult.

Stay enchanted with Ebon Dust Aura at all times, use scythe attack skills as often as necessary to keep Bison virtually always blinded. Mystic Regeneration, Vital Boon, and Signet of Pious Light are your healing skills to keep yourself alive. Scythe attacks do adequate damage to slowly wear Bison down, though the bleeding from Aura of Thorns would hasten it. It is important to not zealously recast enchantments before they expire. Doing so would deprive you of energy gained from Mysticism.

This build has not been tested against: Kilroy, Melonni, Warmaster Tydus

During testing, it was discovered that Mhenlo was only beatable if he did not cast Mending early on in the battle. His Healing Breeze still makes it difficult. It is difficult to beat strong healers such as Danika, but they can be defeated with multiple well timed spikes.

Paragon

 * 14 Spear Mastery
 * 13 Motivation
 * 4 Leadership

Start by quickly charging Barbed Spear, then use it, followed by Maiming Spear to cripple Bison. You can then run around to kite him, periodically stopping to use Barbed Spear and Maiming Spear again. Use Mending Refrain if you get hit, but Maiming Spear lasts long enough that you should rarely get hit other than his initial flurry. Avoid using Stunning Strike or Blazing Spear, as these will lead him to use Purge Signet, and thus remove both bleeding and crippled. You can use Disrupting Throw for its 1/2 second activation time as a quick extra attack to charge Barbed Spear a little faster if needed.

Of all the opponents, only Razah will be troublesome if it lays down spirits of Wanderlust and Shadowsong first. Among those not fought, Danika and the Ghostly Hero look troublesome, the latter because immunity to bleeding really messes up this build.

Opponents not attempted: Kilroy, Danika, Ghostly Hero, Headmaster Vhang, Nika

Other builds
This section is for the various other builds that others have posted on this page. GuildWiki can make no promises about their effectiveness, and only relabeled the headings for truth in advertising on which classes and title tracks are needed.

Assassin
A standard Critical Strike assassin will also beat many opponents, including Magni. You may have to retry should you meet Gwen or some few others, however. Put the maximum you can in Critical Strikes, Daggers at 12 and enough Shadow Arts to get some decent healing from Way of Perfection. Keep the four first effects active at all time (Critical Defenses should take care of itself as it recharges at every critical you land) and everything should be fine: Critical Defenses will stay active throughout the fight, giving a constant 75% block chance, while Way of Perfection should be able to heal whatever gets through. Be aware that Critical Strike is a sure way to both heal you and recharge your energy. Be sure to land the Horns of the Ox/Falling Spider as often as you can.
 * 15 Critical Strikes
 * 12 Dagger Mastery
 * 9 Shadow Arts

Warrior/Necromancer/Norn/Deldrimor
(Also requires a stonefist insignia on a armor piece) This build requires use of a sword.
 * 12+1+1 Swordsmanship
 * 12+1 Strength

This build uses a infinite KD lock to defeat opponents. At the start of the match, you should use enraging charge and go to the opposing fighter and use "You Move Like a Dwarf!" to their interrupt key skills (Ex: Interrupt Norgu's Visions of Regret or Eve's Insidious Parasite ) After, use "For Great Justice!" and Flail. If you use them fast enough, the foe will just be getting up. As soon as you hit the first time, you will gain enough adrenaline to use Brawling Headbutt. Use it, and quickly follow up by Steelfang Slash and Dragon Slash. Repeat the combo until the match is over. (Always keep up flail, and use Plague Touch to pass back any negative conditions.)

Opponents not attempted: Palawa Joko

Link to where the build originated

Warrior/Necromancer/Sunspear
Works very well against melee and OK against the others though you do need to be a bit more careful and watch your timing and bars. The only opponents where this possibly fails is Mhenlo and Argo. When you get to Magni the Bison the easiest approach is to run around until the bear form wears off then turn and face him. You will be able to take him down well before he tries to re-cast.

Warrior/Norn/Ebon Vanguard/Asura
Use Summon Mursaat and Assassin Support. Then run in and attack using defense skills until your energy is at 10. Finish with Ursan Blessing. Be careful of his Irresistible Blow, this will knock you down when blocked.
 * 13 Strength
 * 11 Tactics
 * 11 Swordsmanship

Warrior/Norn
With Bison (and some others like Kahmu) target them as soon as possible and shout "You Move Like a Dwarf!" whilst running in with Enraging Charge, this interrupts bear form / elite form and enchantments.

With melee and melee caster opponents start by alternating Riposte and Deadly Riposte then cast Endure Pain and Dolyak Signet before switching to Ursan Blessing to finish them off.

Ursan will disable enchantments but Endure Pain and Dolyak Signet will remain active during your bear form so cast them just before switching and then pound away with bear attacks.

With pure casters, interrupt, buff and change form as soon as possible.

For the optional skill, either take a pet along for extra damage and the distraction factor, extra damage buffs, self heal skills eg Healing Signet / Lions Comfort or if you are lucky enough to be a necro secondary, a life stealing skill eg Vampiric Gaze for use against Mhenlo.

If you miss with "You Move Like a Dwarf!" first time and have Norn level 5 or greater don't dispair, the recast time is shorter than the duration allowing you to keep Bison crippled long enough to easily keep out of his way until his bear form wears off. If you are lower than 5 run round using Riposte and Deadly Riposte as above or trying to avoid his attacks until bear form runs out.

Ranger/Mesmer/Norn
Use Ursan Blessing for all the fights except Magni. While using it, equip a melee weapon to help you stay in range while using Ursan Rage and Ursan Roar. Spam the first two skills in the Ursan skillbar as often as possible (perhaps timing the knockdowns to interrupt healing). The other 7 skills are needed only to defeat Magni, although they will work on all of the melee opponents. Simply stand at the entrance, far enough out to so that the doors don't close but that if you step forward a little they will. Lay down the two spirits, then use Serpent's Quickness and spam the traps until Energizing Wind dies. Once it is dead recast it and lay down a couple more traps whilst keeping Serpent's Quickness up. Hopefully only ~15 seconds will have past since you recast Energizing Wind... that means you have about 15 seconds to lure Magni onto your traps (easily done). The essential bit here is that you'll need 25 energy spare for your next move. Simply step forward, let the doors close and he will come to you. Once he is within range cast Ignorance (to prevent him removing your lovely conditions) and then Ursan Blessing. Once he gets within melee distance of you simply use Ursan Rage to knock him down and he will be helpless to your traps. If he survives your traps then use your Ursan skills to quickly bring him down the rest of the way.

Ranger/Norn
First, use "I Am The Strongest!" as it has infinite duration. Apply poison, lay Dust Trap, use "You Move Like a Dwarf!" to knock down and cripple him, and shoot Bison with Sloth Hunter's Shot as many times as you can. Keep Shooting him without using any other skills. When he hits the dust trap, he'll be blinded for about 5-12 seconds depending on your Wilderness Survival level. If he uses Purge Signet or blind wears off, use throw dirt until that wears off.

Now for the tricky bit. If "You Move Like a Dwarf!" has recharged or you haven't used it yet, use it now to buy some time. Now you should start running and use Ursan Blessing. Use Ursan Rage along with Ursan Force to knock him down if you can't with YMLaD. Run, and whenever Ursan Rage recharges, use it. But make sure Bison is right behind you. If he is, by the time Rage activates, he will be right next to you and it will knock him down. Keep doing this. When you use Ursan Force, he will run to the opposite side of the arena if you are too far ahead.

Ranger/Warrior/Norn
You will need Pyrebound Insignia
 * Swordsmanship 10
 * Tactics 9
 * Expertise 9+3
 * Wilderness Survival 8+3

Lay Greater Conflagration before entering the arena. Then, run straight in shouting YMLaD as soon as you get in range. This interrupts Bison's Bear Form and important buffs of other opponents. Then use Lightning Reflexes, Riposte, and Deadly Riposte to block most of his attacks while still dealing 50-60 damage. Use Poison Tip Signet to inflict degen (This comes in handy during the first 5 rounds). Use Healing Signet as much as possible, and try to knock Bison down before using it.

Ranger/Ritualist/Sunspear
Use a staff or wand/focus and Radiant/Attunement armor for as much energy as possible. The only truly necessary skills here for defeating Magni are Serpent's Quickness, Shadowsong, and Painful Bond, though using only these skills will take a long time. The remaining skills are for defeating the previous opponents as well as speeding up the process of killing Magni. Activate Serpent's Quickness, then lay all the spirits at the very front of the doorway, BEFORE the doors close. Once all spirits have been activated, run forward enough to aggro the opponent. From there, the spirits will do the killing, though make sure to relay them as necessary. For opponents with AoE (such as Argo), you should let them hit you before they hit the spirits, otherwise the spirits will die and you will be overpowered.
 * 8+4 Expertise
 * 8 Wilderness Survival
 * 11 Communing
 * 9 Channeling Magic

Monk/Assassin
Against any enemy just use the chain, and they should die before using Iron Palm. For Magni, precast Reversal, and cast it once more after Holy Strike, then continue the chain and finish with Reversal. Then kite away and keep casting reversal on recharge. Rinse and repeat.
 * Smiting Prayers 16
 * Deadly Arts 9
 * Dagger Mastery 9

Necromancer/Mesmer/Norn/Ebon Vanguard
Start each round with Signet of Agony and then Arcane Echo before the door even opens. The amazing power of Echoed Assassins should see you through the first six rounds, most fights taking less than ten seconds. Against Bison the most important skill is YMLAD, which will allow you to play keep away and attack with Echoed Angorodons. Grenth's Balance is there for emergencies; if you're feeling brave you can allow Bison to hit you once and then Balance him for a bunch of damage.
 * 16 Blood Magic
 * 12 Curses
 * 5 Norn Rank
 * 5 Ebon Vanguard Rank

Faintheartedness is there so melee chars don't kill off your dual assassins too quickly, and Strip Enchantment is there specifically for Alesia. The only opponents that give this build trouble are Alesia (too much healing, kills assassins quickly) and Gwen (interrupts).

Necromancer/Monk
Based on the 55 monk, this build requires 55 gear.

When entering a new round, cast Mending. Approach the enemy and cast Protective Spirit. Cast Spoil Victor on foe and just wait until he/she dies. If necessary, finish foe with Necrosis. Use Healing Breeze to counter quick damage or health degeneration.

Notes:
 * Mhenlo will only die using Vampiric Gaze. One single cast of that skill should be enough.
 * Use Rend Enchantments on enemies such as dervishes or earth elementals to make them easier to kill.
 * Razah doesn't attack so he'll only go down by spamming Necrosis.
 * Mesmers are easy, just cast Spoil Victor before they can interrupt you. They`ll go down without having to cast any other spell. Use Healing Breeze as a cover enchantment if needed.
 * For Magni, cast Parasitic Bond, wait until he removes it with Purge Signet, then cast Spoil Victor. Recast it when he uses Purge Signet again.

Mesmer/Norn/Ebon Vanguard
Right 4 skills are for Round 1 to Round 5. Cast either resistance before round starts. Ebon Vanguard Assassin Support is not necessary but he does his job and you can cast Ursan Blessing safely. Then you can defeat opponent by using Ursan Skills.

Left 4 skills are for Magni the Bison. After the gate has opened, cast Shrinking Armor to make him use Purge Signet to remove the hex. You can interrupt by using "You Move Like a Dwarf!"，either way he suffers crippled. Then cast Conjure Phantasm to reduce his HP. After that, run and repeat casting "You Move Like a Dwarf!" and Conjure Phantasm. It takes about 3 minutes to defeat him.

Mesmer/Necromancer/Norn/Ebon Vanguard
For most enemies, hitting the first 4 skills in a row and spamming Necrosis kills almost all of them very quickly. With Bison, start with "You Move Like a Dwarf!" to interrupt bear form, then Fetid Ground, Vile Miasma and Necrosis. His purge signet will clear the conditions but they still do a good amount of damage. Kite until the energy is back and repeat. Use Grenth's balance when he gets a few hits in to heal and do damage to him. Ignorance is good if energy permits.
 * 12 Death Magic
 * 9 Fast Casting

Mesmer
Getting there gets a problem with some opponents, such as Razah and Gwen, but almost any other opponent is manageable or quite easy. For Bison, just keep him blinded and under Ignorance and Empathy. Mantra of Inscriptions is used for keeping him blind. Whenever he hits you, start kiting and heal with Ether Feast until you're full health again. He'll eventually die from Empathy.
 * 10+1 Fast Casting
 * 12+3+1 Domination Magic
 * 8 Inspiration Magic

Skill code: OQBDAqwDO6ANwIgD8AAqoAoA

Elementalist/Necromancer/Sunspear
Given that you are inflicting a lot of conditions, Necrosis gives good damage every cast. Just keep him blind/weakened and apply cracked armor as often as you can. Javelin is handy for an interrupt.

The inclusion of Shock or Gale is beneficial against Bison (substitute for javelin). It will give you enough time to re-blind him after purge (or can be used as an interrupt of course).

Elementalist/Necromancer
Before you aggro, cast your Enchantments. AoR is there as a cover, and for self-heal against a random hit from Bison. This build worked against most opponents. For Danika: Wear her out a bit, and when she gets BR'd by Brutus, spike Sheena with Lightning Hammer, Lightning Orb. For Bison: Begin with Enchantments and such. Open your attack chain with Blinding Flash. He will immediately remove it, but that won't matter. Once he is in melee range, your Blinding Flash should be recharged, and thus he won't score a hit. If your Flash is recharged, count to 4 and recast. If you see him casting Purge Signet, or know it's about to come, time a Flash so he had just casted Purge Signet, and is blinded again. If he manages to score a hit, just keep casting, the wounds will heal due to AoR.

Assassin/Dervish/Ebon Vanguard
Most important is blind, it helps greatly against Bison and other martial characters.

By far not a perfect build but it is able to kill everyone, Mhenlo can be hard, but if you are fast enough with twisting fangs he too can be beaten. The rest is a question of spamming Sneak attack and keeping your hp regen skills up which will out-heal most damage.

Assassin/Dervish
Mystic Regeneration, Critical Agility, and Critical Defenses will counter melee opponents. The only tricky fights are Eve and Vhang. Argo flatly cannot be beaten with this build unless you substitute Expunge Enchantments for Fleeting Stability. Gwen also can't be beaten with this build unless you substitute condition removal for Fleeting Stability. For Bison, keep up Fleeting Stability and use Critical Strikes frequently to keep your energy up.
 * 11+2 Dagger Mastery
 * 12+1 Critical Strikes
 * 8 Earth Prayers

Dervish/Assassin
An Ebon Scythe Snathe is needed.

When he purges his blind your enchantments should keep you alive long enough for you to use Mystic Sweep (IF you kept track of the purge recharge and didn't just use it) and blind him again. Use Eternal Aura to Keep up Heart of Fury 3 times in a row.

Paragon/Warrior/Deldrimor/Norn

 * 12 Tactics
 * 12 Spear Mastery
 * 10 Leadership

Keep casters Dazed with Awe and feel free to use both knockdown skills. Immediately knock Bison down with YMLAD to prevent his Bear Form.