Uses of trickster:
Sleep all to steal from mobs.
Slow for bosses, don't give up just because you failed the first time, try it for about four times, after that you'd be able to attack the boss 2-3 times as much as the boss.(Stun works better on most non-post game bosses though)
The armor down and and spirit down is good for the bosses with tons of hp in post game and Final, they add about 30-50% to your damage.
This means that trickster tiers are best left for post game, though they can be helpful for Final.
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