Secondary professions for a Warrior

Warrior/Ranger

 * The Ranger line offers a few alternative IAS skills.
 * Warrior Rangers can make use of the preperation Apply Poison to add the poison Condition to their attacks, however it can desimate a Warriors low energy.

Warrior/Monk

 * Skills such as Mending, which has a small return for a high cost of attribute points and Orison of Healing, which is a mediocre heal, should be avoided. Although when used with skills like Warriors Endurance the energy degeneration can be avoided completely.
 * Mending Touch is a useful form of condition removal, even with little or no attribute point investment.
 * Supporting skills such as Vigorous Spirit provide excellent healing over time, allowing the Warrior to keep on fighting. In addition, Vigorous Spirit can combine well with Cyclone Axe and Triple Chop.

Warrior/Necromancer

 * The most common usage of the Necromancer secondary is for condition removal via Plague Touch.
 * Aside from this, a Warrior willing to spend 10 energy can add the Barbs hex to there enemy for additional physical damage bonus

Warrior/Mesmer

 * Wise use of Physical Resistance, Elemental Resistance or elemental mantras can add additional survivability to solo or tanking builds.

Warrior/Elementalist

 * Shock can be used as a snare and interrupt, however exhaustion will certainly be felt with a Warrior's low energy pool.
 * Grasping Earth can be used as an AoE snare to keep groups of enemies from kiting as efficiently.
 * The conjure skills, such as Conjure Frost can provide additional damage when wielding an elemental weapon for a very small investment of energy.
 * Defensive Earth Magic enchantments such as Obsidian Flesh and Stoneflesh Aura can be used for tanking in high-end areas such as the Domain of Anguish, however their high Energy cost requires Energy support from an ally such as a BiP Necromancer.

Warrior/Assassin

 * The Assassin has a wide range of snares and shadow steps that can serve a Warrior well. Shadow Prison for example.
 * Signet of Malice can provide free condition removal.
 * Dash is an excellent speed boost that also serves as a quickly recharging cancel stance for Frenzy.
 * Death's Charge is useful for closing distance in battle, but take care not to outrun your party's support.
 * Disrupting Dagger is a useful interrupt which cannot be blocked or miss.

Warrior/Ritualist

 * Sparing use of Weapon skills can benefit a Warrior; Splinter Weapon can be combined with Triple Chop or Hundred Blades. Ritualist primaries, however, far outclass Warriors at spamming weapon spells.

Warrior/Paragon
Warrior and Paragon skills have very little synergy, the best combination for the two is the combination of Tactics and Command Shouts.
 * Warriors can use the shout "Can't Touch This!" to negate the effects of or Plague Touch or other such skills.

Warrior/Dervish

 * A scythe can work in a Steady Stance/Drunken Blow/Desperation Blow build.
 * Many Scythe Mastery skills are general-purpose Melee Attacks (i.e. Rending Sweep) rather than weapon-specific skills, which allows them to be used with axes, hammers, and swords.
 * Rending Touch can be used as an enchant removal.
 * Pious Haste can be used as a cancel-stance for Frenzy.