The Great Learner (5e Feat)
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The Great Learner
You can spend 2 hours, as part of your long rest, to study a new feat or spell, skill proficiency or tool proficiency. To be able to do so, you must have a creature with access to the desired skill feat or spell, that also must spend the next 2 hours teaching you.
If you are trying to learn a new spell, the spell must be part of your class spell list and you must have a spell slot with the appropriated level to cast it.
You can also replace an Ability Score Improvement you have taken by a feat or an Ability Score Improvement taken by the creature teaching you.
When you finish the long rest, you can replace one skill, feat or spell you have for the new skill, spell or feat taught to you. You can't replace this feat with this ability.