Trick
When picking the specialization the Mischief-maker, a Burglar can earn four Trick skills which debuff enemies:
Trick: Counter Defence lowers the Avoidance ratings and Critical Defence of a single target.
Trick: Disable lowers the damage and increases the attack duration of a single target.
Trick: Dust in the Eyes slows and increases the miss chance of up to three targets.
Trick: Enrage increases the incoming damage, and disables most ranged attacked of a single target
Only one Trick can be active on a target, though after using the skill 
Trickster, you can temporarily apply one additional Trick.
Trickster also make Tricks AoE for two additional targets in range. If you have the tracery Area Effect Target Count slotted on your legendary item, an additional 4 targets can be tricked, making Enrage for instance max 7 targets, and Dust in the Eyes even 9.
Trick Removal skills remove active Tricks on a target in return for activating other effects:
Mischievous Glee removes 1 Trick and heals 10% of your maximum Morale. The improved version 
Mischievous Delight also heals your fellows and restores a small amount of Power over time.
Startling Twist removes one Trick, stuns the enemy and removes Corruptions. The improved version 
Improved Startling Twist can target up to three enemies (.
Clever Retort removes all Tricks and performs a 'fake Fellowship Manoeuvre'. Depending on the Trick(s) that is (are) removed, you deal direct damage, apply a bleed, get an AoE Morale heal or get an AoE Power heal (see skill page for more information).
The first two skills always remove a "non-Trickster Trick". This implies that if you remove a Trick from a target with two Tricks on it using Mischievous Glee or Startling Twist, you can immediately apply a new Trick.