Feather, Radiant Arbiter {R}{W}{W}
Legendary Creature — Angel
Identity
Boros
EDHREC rank
#14,545
Cheapest printing
US$0.38
TCGplayer
Printings
2
Flying, lifelink
Whenever you cast a noncreature spell that targets only Feather, you may choose any number of other creatures that spell could target and pay {2} for each of those creatures. If you do, for each of those creatures, copy that spell. The copy targets that creature. (Copies of permanent spells become tokens.)
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.