Ob Nixilis, Unshackled {4}{B}{B}
Legendary Creature — Demon
BlackCommander: legal
Identity
Black
EDHREC rank
#4,024
Cheapest printing
US$3.99
TCGplayer
Printings
4
Flying, trample
Whenever an opponent searches their library, that player sacrifices a creature of their choice and loses 10 life.
Whenever another creature dies, put a +1/+1 counter on Ob Nixilis.
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.