Roshan, Hidden Magister {3}{B}
Legendary Creature — Human Assassin
BlackCommander: legal
Identity
Black
EDHREC rank
#7,177
Cheapest printing
US$0.26
TCGplayer
Printings
3
Other creatures you control are Assassins in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
Face-down creatures you control have menace.
Whenever a permanent you control is turned face up, you draw a card and you lose 1 life.
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.