If you're using EnchantedBosses / EnchantedCombat, use a version before 8.x.x

This is a library that unlocks the ability for more powerful conditions in my Superheroes plugin, as well as being essential for SuperheroesPlusUltra, EnchantedBosses and EnchantedCombat.

I recommend downloading from modrinth as more likely to be up to date: https://modrinth.com/plugin/skillslibrary/version/5.1.0