the binding of isaac four souls requiem cards Isaac: Card Game: Ultimate Collection – Asmodee USA as well as the optional Room Deck The Lost - Four Souls

Lo and Li, Royal Advisors Lo and Li, Royal Advisors are mill on demand, very similar to Oona, Queen of the Fae

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Since you have access to some of the best lifegain, phyrexian mana could have made the list, but I think that takes it too far

They're not all red either, I promise, the colorless card, Chalice of Life / Chalice of Death is a clean win condition if your opponent's creatures can't attack

Most instances of either gating condition are on activated abilities (most of which don't cost mana and therefore need a limiting condition), neatly solving the issue I'm about to mention, but consider this example: We're playing Innistrad Crimson Vow draft