Magic Rats

Makes it where every naturally generated rat in Mines is replaced by a custom rat variant with access to random spellbooks. Rats have an equal chance to spawn with: Forcebolt, Magic Missle, Cold, Fireball, Lightning, Sleep, Confuse, Slow, Bloodletting, Acid Spray, Steal Weapon, Drain Soul, Charm, Spray Web, Poison No, they do not drop the spellbooks on death. Only rats from the mines get turned into magic rats, scrolls of summon/other sources will not work. This is because the magic rat is a custom monster. To summon a magic rat with commands, do /summon magic_rat