Monster Trainer
* Starts with 6 capture balls, a small item that is stored in your inventory
* When a monster is reduced to 10% or lower health, a capture ball can be used on it to capture it. You do not get XP.
* Monsters trapped in capture balls continue to heal as normal when tiles are explored
* Monsters trapped in a capture ball can be used to fight other monsters, dealing and taking normal damage
* If a monster in a capture ball lands a killing blow against another monster, it gains XP and can potentially level up (same formula as the player).
* When a captured monster dies, both it and its capture ball are lost forever