Yoink!

Yoink! is 's in Xenoblade Chronicles. It has a random effect that includes taking items, stat boosts, or points from the target.

Overview
While Yoink!'s effect is very random, it is always beneficial, and thus should be used as often as possible. Its item-stealing ability makes it a common way to take loot from enemies without having to kill them in an attempt to farm things.

Additional data
The possible effects of Yoink are: Riki cannot steal items, AP, or EXP from enemies that are 11 or more levels above him.
 * HP - Riki steals 50% of his max HP from the enemy, essentially dealing that much damage and healing himself for the same.
 * Strength - Riki gets +10%, while the enemy gets  +10%, with indefinite duration. If triggered multiple times, Riki can get up to a 50% boost while the enemy can get up to a 30% loss.
 * Ether - Riki gets +10%, while the enemy gets  +10%, with indefinite duration. If triggered multiple times, Riki can get up to a 50% boost while the enemy can get up to a 30% loss.
 * Agility - Riki gets +10%, while the enemy gets  +10%, with indefinite duration. If triggered multiple times, Riki can get up to a 50% boost while the enemy can get up to a 50% loss.
 * Item - Riki steals an item from the foe. It is believed the chance of getting any item is the same as if a chest with a single item were dropped. Riki is capable of stealing from enemies that do not normally drop chests but do have items. Up to 4 items can be stolen per battle, which are obtained when the battle ends in victory or escape (but not defeat).
 * AP - Every member of the party gains 50% of the AP the enemy would normally grant. Requires the AP for All! skill.
 * EXP - Every member of the party gains 50% of the EXP the enemy would normally grant. Requires the EXP for All! skill.

The relative probabilities of each effect triggering are unknown. Some enemies are immune to items being stolen, but this mechanism is also unknown.