
The "legend rule" doesn't apply to Slivers you control.
Each Sliver creature card in your graveyard has encore {X}, where X is its mana value.
Encore {5} ({5}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)
Sliver Gravemother has 3 printings, first in Commander Masters (2023). EDHREC ranks it #6,364 among Commander cards. It appears most in The First Sliver decks (11,116 on EDHREC). 1 public deck on TCG runs it. It has 10 official rulings.
Deck counts from EDHREC.
Cards that show up in the same decks on EDHREC.