mtg raptor cards Wizards of the Coast Ripjaw each other Dinosaur you control enters the battlefield with a counter of that kind on it. Frenzied Raptor

However, while self-milling is quite popular in Commander, there are quite a few self-mill commanders to choose from

If you play the card as an omen, shuffle it back into your library after it resolves instead of putting it in your graveyard like you normally would

Cards that get better when you cast or control permanents you dont own, like Agent of Treachery, are good in these situations

Instead of being dealt damage via poison counters to the player and -1/-1 counters to creatures like infect, toxic deals combat damage normally while also giving a poison counter to the player should it do damage

If that creature card has flash, you'll be able to cast it any time you could cast an instant, even on an opponent's turn