Aveline de Grandpré {2}{G}{G}
Legendary Creature — Human Assassin
Identity
Golgari
EDHREC rank
#7,550
Cheapest printing
US$0.46
TCGplayer
Printings
3
Deathtouch
Whenever a creature you control with deathtouch deals combat damage to a player, put that many +1/+1 counters on that creature.
Disguise {B}{G} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
Keywords: disguise, deathtouch
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.