There are many cool things you can do in an Agatha deck, and if you want to read more, I did a deep dive you can find below
Im a big fan of having lots of pinpoint removal spells, especially ones that are instant-speed since you never know when you might need to handle a problem permanent without necessarily sweeping the battlefield, and Generous Gift covers a lot of potential problems
Whatever your preferred frame of reference on this question, we race past milestones
Win at instant speed in your end step
This is because Auras target a creature to enchant them - meaning Killian discounts that spell by two mana
It is a Black recursion-aggro build: send Wano characters to the trash, then replay them with Rush for attacks the opponent does not see coming, all backed by Black's removal