Sivriss, Nightmare Speaker {3}{B}
Legendary Creature — Snake Cleric Warlock
BlackCommander: legal
Identity
Black
EDHREC rank
#9,843
Cheapest printing
US$0.10
TCGplayer
Printings
3
{T}, Sacrifice another creature or an artifact: For each opponent, you mill a card, then return that card from your graveyard to your hand unless that player pays 3 life. (To mill a card, put the top card of your library into your graveyard.)
Choose a Background (You can have a Background as a second commander.)
Keywords: choose a background, mill
Every printing
highest TCGplayer market first; a card with only a thin single listing shows its low
In short
A Commander deck is a commander and 99 other cards, one copy of each (except basic lands), all inside the commander's colour identity. Paste a full list into the deck price calculator to price it and check it against the format.