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To get health:
int enemyHealth = PetBattles.GetHealth(PetBattles.PetFaction.Enemy, PetBattles.GetActivePet(PetBattles.PetFaction.Enemy));
int enemyMaxHealth = PetBattles.GetMaxHealth(PetBattles.PetFaction.Enemy, PetBattles.GetActivePet(PetBattles.PetFaction.Enemy));
int enemyMaxPercent = enemyHealth * 100 / enemyMaxHealth;