Markdown is supported: **bold**, lists with -, headings with #
Oathbreaker is multiplayer format, played with 60 card singleton decks (only one copy of each card, no limit on basic lands).
You start the game with your Oathbreaker and Signature Spell in the command zone.
Your starting life is 20 .
Your “Oathbreaker” is a Planeswalker. Its color identity determines the contents of your deck.
Your “Signature Spell” must be an instant or sorcery card that falls within your Oathbreaker’s color identity.
You cast your Oathbreaker from your command zone.
Your Signature Spell may only be cast if your Oathbreaker is on the battlefield under your control.
Both your Oathbreaker and Signature Spell are subject to “command zone tax”. These taxes are tracked individually, i.e. casting your Oathbreaker doesn’t cause your Signature Spell to cost more.
Full rules: https://oathbreakermtg.org/rules/