Monster girls can boost the experience level by killing mobs. When a monster girl kills a mob, the experience will
not drop as orbs, but directly be given to the monster girl. The XP amount requirement for each level is the same as players.
The experience can also repair the monster girl's equipment with Mending enchantment.
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Each experience level provides extra max HP by 1 and attack by 0.1. When it dies, a half of the experience will be lost.
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Note that the monster girls will not attack the unfriendly monster girls of the same type.
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When a monster girl dies, a Respawner will be generated and given to its owner, for respawning the monster girl.