CLICK_LEFT - Performs the action on left click.
CLICK_RIGHT - Performs the action on right click.
CLICK_EITHER - Performs the action on either click.
CLICK_LEFT_BLOCK - Performs the action on left click of a block.
CLICK_RIGHT_BLOCK - Performs the action on right click of a block.
CLICK_EITHER_BLOCK - Performs the action on either click of a block.
CLICK_LEFT_AIR - Performs the action on left clock of air.
CLICK_RIGHT_AIR - Performs the action on right click of air.
CLICK_EITHER_AIR - Performs the action on either click of air.
ENTITY_RIGHT - Performs the action when an entity is right clicked.
ENTITY_LEFT - Performs the action when an entity is hit.
ENTITY_PROJECTILE - Performs the action when an entity is hit by an arrow (Or other projectile)
ENTITY_EITHER - Performs the action when an entity is either right clicked or hit.
BLOCK_BREAK - Performs the action when a block has been broken.
BLOCK_PLACE - Performs the action when a block has been placed.
BLOCK_PROJECTILE_AIR - Performs the action when a projectile stops moving, but is in air.
BLOCK_PROJECTILE_BLOCK - Performs the action when a projectile hits a block.
BLOCK_PROJECTILE_EITHER - Performs the action when a projectile stops.
BLOCK_EITHER - Performs the action when a block has been either placed or broken.
ITEM_CONSUME - Performs the action when an item is consumed (eaten/drunk).
ITEM_DROP - Performs the action when an item is dropped.
ITEM_BREAK - Performs the action when an item breaks due to durability.
ITEM_PICKUP - Performs the action when an item is picked up.
ITEM_CLICK_LEFT - Performs the action when an item is left clicked in the inventory.
ITEM_CLICK_RIGHT - Performs the action when an item is right clicked in the inventory.
ITEM_CLICK_EITHER - Performs the action when an item is clicked either way in the inventory.
PLAYER_DEATH - Performs the action when the player dies.
PLAYER_CHAT - Performs the action when the player sends a chat message.
PASSIVE - Performs the action every half second. Using cooldowns it is possible to delay this.
          (Cooldown messages aren't displayed for Passive events)
          Passive is also called for equipped armour as well as held item.
ANY - Performs the action when any of the above criteria have been met.