The best best and the broken builds are based arround power, condi thief might be the only Exception, but it's in terms of what it does mostly. Similar to power thief (kill while You Plus fast)
Condi builds can be in lower leagues very strong, but there is enaugh counterplay not only condi cleanses, you can los and not move(torment), run away and don't attack (confusion), not standing in aoes that gives conditions, dodging the attacks is obviously working too.