As long as you control a Jace planeswalker, Jace's Sentinel gets +1/+0 and can't be blocked.

Whenever Jackal Pup is dealt damage, it deals that much damage to you.

Whenever another artifact enters the battlefield under your control, put a +1/+1 counter on Jackknight. If that artifact is a Contraption, Jackknight gains lifelink until end of turn.

: Draw a card, then exile a card from your hand face down. You may look at that card for as long as it remains exiled. You may pay . If you do, transform Jacob Hauken, Inspector.

At the beginning of your end step, if you control no creatures with decayed, create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)

Defender

Landfall — Whenever a land enters the battlefield under your control, you gain 1 life.

When Jade Bearer enters the battlefield, put a +1/+1 counter on another target Merfolk you control.

Green spells you cast cost more to cast.

When Jadecraft Artisan enters the battlefield, target creature gets +2/+2 until end of turn.

When Jaded Sell-Sword enters the battlefield, if mana from a Treasure was spent to cast it, it gains first strike and haste until end of turn.

When Jadelight Ranger enters the battlefield, it explores, then it explores again. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard. Then repeat this process.)

Discard a card: Return Jadzi, Oracle of Arcavios to its owner's hand.

Magecraft — Whenever you cast or copy an instant or sorcery spell, reveal the top card of your library. If it's a nonland card, you may cast it by paying rather than paying its mana cost. If it's a land card, put it onto the battlefield.

Jagged-Scar Archers's power and toughness are each equal to the number of Elves you control.

: Jagged-Scar Archers deals damage equal to its power to target creature with flying.

Tokens you control have ": Add ."

Choose a Background (You can have a Background as a second commander.)

, : Shuffle Jalum Grifter and two lands you control face down. Target opponent chooses one of those cards. Turn the cards face up. If they chose Jalum Grifter, sacrifice it. Otherwise, destroy target permanent.

Trample

Whenever you cast a historic spell, Jamie McCrimmon gets +X/+X until end of turn, where X is that spell's mana value. (Artifacts, legendaries, and Sagas are historic.)

Doctor's companion (You can have two commanders if the other is the Doctor.)

Haste

, Sacrifice an artifact creature: Create two Treasure tokens.

, Sacrifice a noncreature artifact: Create two 1/1 colorless Construct artifact creature tokens.

When Janjeet Sentry enters the battlefield, you get (two energy counters).

, Pay : You may tap or untap target artifact or creature.

Remove a ki counter from Jaraku the Interloper: Counter target spell unless its controller pays .

Whenever Jareth, Leonine Titan blocks, it gets +7/+7 until end of turn.

: Jareth gains protection from the color of your choice until end of turn.

(CARDNAME isn't a spell, it's affected by summoning sickness, it's blue, and it has ": Add .")

CARDNAME enters the battlefield tapped.

CARDNAME doesn't untap during your untap step.

At the beginning of your upkeep, you may pay . If you do, untap CARDNAME.

: Add . Spend this mana only to cast creature spells with no abilities.

Creatures you control with no abilities can't be blocked by creatures with abilities.

Whenever a Zombie or Mutant you control dies, if its power was different from its base power, draw a card.

Come Fly With Me — , Sacrifice a creature: Put a +1/+1 counter on target creature you control. It gains flying until end of turn.

Double strike

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

, , Discard a card: Create a token that's a copy of another target creature you control. It gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step. Activate only as a sorcery.

Blitz (If you cast this spell for its blitz cost, it gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step.)

Flying, haste

Whenever Jaya's Phoenix deals combat damage to a player or planeswalker, copy the next loyalty ability you activate this turn when you activate it. You may choose new targets for the copy.

Whenever you cast a planeswalker spell, you may return Jaya's Phoenix from your graveyard to the battlefield.

Whenever Jedit Ojanen, Mercenary or another legendary creature enters the battlefield under your control, you may pay . If you do, create a 2/2 green Cat Warrior creature token with forestwalk. (It can't be blocked as long as defending player controls a Forest.)

When Jeering Homunculus enters the battlefield, you may goad target creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Companion — No card in your starting deck has more than one of the same mana symbol in its mana cost. (If this card is your chosen companion, you may put it into your hand from outside the game for as a sorcery.)

: Add . This mana can't be spent to pay generic mana costs.

Flying

When Jeleva, Nephalia's Scourge enters the battlefield, each player exiles the top X cards of their library, where X is the amount of mana spent to cast Jeleva.

Whenever Jeleva attacks, you may cast an instant or sorcery spell from among cards exiled with Jeleva without paying its mana cost.

Flying

: Put a +1/+1 counter on Jenara, Asura of War.

Double strike

Whenever Jenny deals combat damage to a player, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

First strike, haste

: Jeska, Warrior Adept deals 1 damage to any target.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Whenever Jeskai Elder deals combat damage to a player, you may draw a card. If you do, discard a card.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

When Jeskai Sage dies, draw a card.

Flying

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Creatures you control get +1/+0 and have vigilance as long as you control three or more creatures.

Creatures you control also get +1/+0 and have trample as long as you control six or more creatures.

Creatures you control also get +1/+0 and have double strike as long as you control nine or more creatures.

Alpha strike (This creature has first strike as long as it's blocking or being blocked by a creature that comes after it alphabetically.

Vigilance, trample

When Jewel Thief enters the battlefield, create a Treasure token. (It's an artifact with ", Sacrifice this artifact: Add one mana of any color.")

Deathtouch

When Jewel-Eyed Cobra dies, create a Treasure token. (It's an artifact with ", Sacrifice this artifact: Add one mana of any color.")

Jhessian Infiltrator can't be blocked.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Whenever Jhessian Thief deals combat damage to a player, draw a card.

, Exile a nonland card from your hand: Put four time counters on the exiled card. If it doesn't have suspend, it gains suspend. (At the beginning of your upkeep, remove a time counter from that card. When the last is removed, you may cast it without paying its mana cost. If it's a creature, it has haste.)

Whenever you cast a historic spell, draw a card. (Artifacts, legendaries, and Sagas are historic.)

: Choose target permanent you control or suspended card you own. If that permanent or card has a time counter on it, you may remove a time counter from it or put another time counter on it.

Vigilance

Ward

Whenever you cast a noncreature spell with mana value 3 or greater, draw a card.

: Exile Jin-Gitaxias, then return it to the battlefield transformed under its owner's control. Activate only as a sorcery and only if you have seven or more cards in hand.

Whenever you cast an artifact, instant, or sorcery spell, copy that spell. You may choose new targets for the copy. This ability triggers only once each turn. (A copy of a permanent spell becomes a token.)

Whenever an opponent casts an artifact, instant, or sorcery spell, counter that spell. This ability triggers only once each turn.