Kethis, the Hidden Hand {W}{B}{G}
Legendary Creature — Elf Advisor
Identity
Abzan
EDHREC rank
#7,506
Cheapest printing
US$3.75
TCGplayer
Printings
3
Legendary spells you cast cost {1} less to cast.
Exile two legendary cards from your graveyard: Until end of turn, each legendary card in your graveyard gains "You may play this card from your graveyard."
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.