
You may mill three cards. Then return a creature card from your graveyard to the battlefield. (To mill a card, put the top card of your library into your graveyard.)
Summon Undead has 3 printings, first in Commander Legends: Battle for Baldur's Gate (2022). EDHREC ranks it #14,570 among Commander cards. It appears most in Bartolomé del Presidio decks (214 on EDHREC). It has 3 official rulings.
Deck counts from EDHREC.
Cards that show up in the same decks on EDHREC.