Bukkit

List of raw effects here

ADD_POTION,
REMOVE_POTION,
ADD_HEALTH,
REMOVE_HEALTH,
SET_HEALTH,
ALLOW_FLIGHT
, DENY_FLIGHT,
EXECUTE_COMMAND,
BROADCAST_MESSAGE,
EXPLODE,
SHOOT_ENTITY,
SPAWN_ENTITY,
ADD_ITEM,
REMOVE_ITEM,
DROP_ITEM,
ADD_EXP,
REMOVE_EXP,
DROP_EXP;