Character level

In any role-playing game, character level is a general indication of how powerful a character is. Two characters who are the same level will, in general, be able to compete against each other.

Player characters in Guild Wars have a maximum level of 20. Unlike other MMORPGs, this level cap isnâ€™t a barrier to character development. Level 20 player-characters will still earn additional skill points and be able to learn new skills, although additional health and attribute points are no longer acquired.

Damage that depends on Level:
Damage done by skills and wands (and any other magical projectile weapon) is dependant to your character level. You do 100% damage at level 20 (if your terget's AL is exactly 60), and less damage the lower your level is. This however does not apply to skills that ignore armor, the always do listed damage, and thus your character level is never taken into account.

Formula: actual_damage = Damage*2^ ((caster_level*3 -AL*(1-penetration/100))/40)