When Oath of Gideon enters the battlefield, create two 1/1 white Kor Ally creature tokens. Each planeswalker you control enters the battlefield with an additional loyalty counter on it.
When Oath of Jace enters the battlefield, draw three cards, then discard two cards. At the beginning of your upkeep, scry X, where X is the number of planeswalkers you control.
"For the sake of the Multiverse, I will keep watch."
When Oath of Kaya enters the battlefield, it deals 3 damage to any target and you gain 3 life. Whenever an opponent attacks a planeswalker you control with one or more creatures, Oath of Kaya deals 2 damage to that player and you gain 2 life.
"So everyone gets what they truly deserve, I will keep watch."
When Oath of Liliana enters the battlefield, each opponent sacrifices a creature. At the beginning of each end step, if a planeswalker entered the battlefield under your control this turn, create a 2/2 black Zombie creature token.
When Oath of Nissa enters the battlefield, look at the top three cards of your library. You may reveal a creature, land, or planeswalker card from among them and put it into your hand. Put the rest on the bottom of your library in any order. You may spend mana as though it were mana of any color to cast planeswalker spells.
When Oath of Teferi enters the battlefield, exile another target permanent you control. Return it to the battlefield under its owner's control at the beginning of the next end step. You may activate the loyalty abilities of planeswalkers you control twice each turn rather than only once.
Oathsworn Knight enters the battlefield with four +1/+1 counters on it. Oathsworn Knight attacks each combat if able. If damage would be dealt to Oathsworn Knight while it has a +1/+1 counter on it, prevent that damage and remove a +1/+1 counter from it.
[+1]: You draw a card and you lose 1 life. [–3]: Destroy target creature. [–8]: Target opponent gets an emblem with "Whenever a player draws a card, you lose 2 life."
[+2]: Each opponent loses 1 life. You gain life equal to the life lost this way. [–2]: Create a 5/5 black Demon creature token with flying. You lose 2 life. [–8]: You get an emblem with "{1}{B}, Sacrifice a creature: You gain X life and draw X cards, where X is the sacrificed creature's power." Ob Nixilis of the Black Oath can be your commander.
Flying, trample Whenever one or more opponents each lose exactly 1 life, put a +1/+1 counter on Ob Nixilis, Captive Kingpin. Exile the top card of your library. Until your next end step, you may play that card.
Flying, trample Whenever an opponent searches their library, that player sacrifices a creature and loses 10 life. Whenever another creature dies, put a +1/+1 counter on Ob Nixilis, Unshackled.
Casualty X. The copy isn't legendary and has starting loyalty X. [+1]: Each opponent loses 2 life unless they discard a card. If you control a Demon or Devil, you gain 2 life. [–2]: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target." [–7]: Target player draws seven cards and loses 7 life.
Whenever an opponent draws a card, Ob Nixilis, the Hate-Twisted deals 1 damage to that player. [–2]: Destroy target creature. Its controller draws two cards.
{1}{W}, {T}: You gain 5 life. {1}{U}, {T}: Draw a card, then discard a card. {1}{B}, {T}: Target creature gets -2/-2 until end of turn. {1}{R}, {T}: Obelisk of Alara deals 3 damage to target player or planeswalker. {1}{G}, {T}: Target creature gets +4/+4 until end of turn.
When Oblivion Ring enters the battlefield, exile another target nonland permanent. When Oblivion Ring leaves the battlefield, return the exiled card to the battlefield under its owner's control.
When you cast this spell, target opponent exiles the top four cards of their library, then you may put any number of land cards that player owns from exile onto the battlefield under your control.
The Eldrazi hunger without limit and consume without pause.
{4}, {T}: Put a fate counter on target permanent. {5}, {T}, Sacrifice Oblivion Stone: Destroy each nonland permanent without a fate counter on it, then remove all fate counters from all permanents.
Companion — Your starting deck contains only cards with odd mana values and land cards. If a source you control with an odd mana value would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.
Whenever you cast a spell, if its mana value is equal to 1 plus the number of soul counters on Obscura Ascendancy, put a soul counter on Obscura Ascendancy, then create a 2/2 white Spirit creature token with flying. As long as there are five or more soul counters on Obscura Ascendancy, Spirits you control get +3/+3.
Choose one — • Return target multicolored permanent card with mana value 3 or less from your graveyard to the battlefield tapped. • Counter target instant or sorcery spell. • Destroy target creature or planeswalker with mana value 3 or less.
Choose three. You may choose the same mode more than once. • Until end of turn, target creature loses all abilities and has base power and toughness 1/1. • Target creature connives. • Target player returns a creature card from their graveyard to their hand.