Omarthis, Ghostfire Initiate {X}{X}
Legendary Creature — Spirit Snake
ColorlessCommander: legal
Identity
Colorless
EDHREC rank
#8,777
Cheapest printing
US$1.33
TCGplayer
Printings
2
Omarthis enters with X +1/+1 counters on it.
Whenever you put one or more +1/+1 counters on another colorless creature, you may put a +1/+1 counter on Omarthis.
When Omarthis dies, manifest a number of cards from the top of your library equal to the number of counters on it.
Keywords: manifest
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.