Peri Brown {3}{W}
Legendary Creature — Human
WhiteCommander: legal
Identity
White
EDHREC rank
#13,767
Cheapest printing
US$0.26
TCGplayer
Printings
4
The first historic spell you cast each turn has convoke. (Your creatures can help cast it. Each creature you tap while casting it pays for {1} or one mana of that creature's color.)
Doctor's companion (You can have two commanders if the other is the Doctor.)
Keywords: doctor's companion
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.