Cheap cards aren't always the best ink
Learn was showcased on the Pop Quiz card, which lets players draw a card before also Learning - which is either discarding a card to draw a card, or fetching a Lesson from "outside the game" (in play, this means the player's sideboard)
Ive watched videos and streams where players try to draw cards against her, Ive attempted it myself, and Ive had a Narset out when an opponent tried to draw cards at least 100 times in total
Notably, this card has no limitations, so if youve spent your turn producing ample Elf tokens or dropping tons of one-drop Elves (both examples with summoning sickness), you can tap them all down for loads of mana
For example, if Vincent's power was 7 when it dealt combat damage to an opponent but is reduced to 6 just before its last ability resolves, it won't deal any additional damage when the last ability resolves