Avacyn, Guardian Angel {2}{W}{W}{W}
Legendary Creature — Angel
WhiteCommander: legal
Identity
White
EDHREC rank
#14,688
Cheapest printing
US$1.64
TCGplayer
Printings
1
Flying, vigilance
{1}{W}: Prevent all damage that would be dealt to another target creature this turn by sources of the color of your choice.
{5}{W}{W}: Prevent all damage that would be dealt to target player or planeswalker this turn by sources of the color of your choice.
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.