Bukkit

Added the ability to have Mobs deal custom effects to the player on hitting him/her.

You can add Potion Effects to the mobs in a greater variety.

Fixed a massive bug with the spawner egg spawning.

Added the ability for you to give players achievements for killing the Custom Mob.

You can even have it so when the mob his the player it changes his game mode!

None currently. Please report if found.