First strike, vigilance

Akiri, Line-Slinger gets +1/+0 for each artifact you control.

Partner (You can have two commanders if both have partner.)

Flying, first strike, vigilance, trample

At the beginning of each combat, until end of turn, each other creature you control gets +1/+1 if it has flying, +1/+1 if it has first strike, and so on for double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, protection, reach, trample, vigilance, and partner.

Partner

First strike

{T}: Add an amount of {R} equal to the greatest power among creatures you control that entered the battlefield this turn.

Partner (You can have two commanders if both have partner.)

When Alharu, Solemn Ritualist enters the battlefield, put a +1/+1 counter on each of up to two other target creatures.

Whenever a nontoken creature you control with a +1/+1 counter on it dies, create a 1/1 white Spirit creature token with flying.

Partner (You can have two commanders if both have partner.)

As long as it's your turn, commanders you control have indestructible. (Effects that say "destroy" don't destroy them. A creature with indestructible can't be destroyed by damage.)

Partner (You can have two commanders if both have partner.)

At the beginning of combat on your turn, you may attach any number of Auras and Equipment you control to target permanent or player.

Partner (You can have two commanders if both have partner.)

Whenever Armix, Filigree Thrasher attacks, you may discard a card. When you do, target creature defending player controls gets -X/-X until end of turn, where X is the number of artifacts you control plus the number of artifact cards in your graveyard.

Partner (You can have two commanders if both have partner.)

Menace

Whenever one or more Pirates you control deal damage to your opponents, exile the top card of each of those opponents' libraries. You may play those cards this turn, and you may spend mana as though it were mana of any color to cast those spells.

Partner (You can have two commanders if both have partner.)

When Brinelin, the Moon Kraken enters the battlefield or whenever you cast a spell with mana value 6 or greater, you may return target nonland permanent to its owner's hand.

Partner (You can have two commanders if both have partner.)

Whenever Bruse Tarl, Boorish Herder enters the battlefield or attacks, target creature you control gains double strike and lifelink until end of turn.

Partner (You can have two commanders if both have partner.)

As an additional cost to cast this spell, you may sacrifice any number of artifacts and/or creatures. This spell costs {2} less to cast for each permanent sacrificed this way and {2} less to cast for each other artifact or creature you've sacrificed this turn.

Trample

Partner (You can have two commanders if both have partner.)

Flying

If you would scry a number of cards, draw that many cards instead.

Partner (You can have two commanders if both have partner.)

Flying

Spells your opponents cast that target one or more commanders you control cost {3} more to cast.

Partner (You can have two commanders if both have partner.)

Commanders you control have menace and deathtouch.

Partner (You can have two commanders if both have partner.)

As Fluros of Myra's Marvels enters the battlefield, choose a number greater than 0.

Whenever you cast a spell with power, toughness, or loyalty equal to the chosen number, target artifact or creature becomes an artifact creature with base power and toughness X/X until end of turn, where X is the chosen number.

Partner

Flying

Francisco, Fowl Marauder can't block.

Whenever one or more Pirates you control deal damage to a player, Francisco explores.

Partner (You can have two commanders if both have partner.)

Ghost of Ramirez DePietro can't be blocked by creatures with toughness 3 or greater.

Whenever Ghost of Ramirez DePietro deals combat damage to a player, choose up to one target card in a graveyard that was discarded or put there from a library this turn. Put that card into its owner's hand.

Partner (You can have two commanders if both have partner.)

{T}: Add {G}. When you spend this mana to cast a spell with mana value 6 or greater, draw a card.

Partner (You can have two commanders if both have partner.)

{T}, Tap X untapped artifacts you control: Look at the top X cards of your library. Put one of those cards into your hand and the rest into your graveyard.

Partner (You can have two commanders if both have partner.)

Reach

Whenever another creature enters the battlefield under your control, you may pay {2}. When you do, that creature deals damage equal to its power to target creature.

Partner (You can have two commanders if both have partner.)

As Hardy of Myra's Marvels enters the battlefield, choose a number.

Whenever you cast a spell with the chosen number of lines of flavor text, put that many +1/+1 counters on target creature.

Partner (You can have two commanders if both have partner.)

When Ich-Tekik, Salvage Splicer enters the battlefield, create a 3/3 colorless Phyrexian Golem artifact creature token.

Whenever an artifact is put into a graveyard from the battlefield, put a +1/+1 counter on Ich-Tekik and a +1/+1 counter on each Golem you control.

Partner (You can have two commanders if both have partner.)

As Ignacio of Myra's Marvels enters the battlefield, choose armor, blood, book, bottle, fang, fire, scroll, spear, sword, or water.

Whenever you cast a spell with the chosen object in its art, create two Treasure tokens.

Partner (You can have two commanders if both have partner.)

Menace

Whenever a creature you control deals combat damage to a player, you gain life equal to that creature's toughness.

Partner (You can have two commanders if both have partner.)

Flying

Whenever an opponent casts a spell, put a +1/+1 counter on Ishai, Ojutai Dragonspeaker.

Partner (You can have two commanders if both have partner.)

Jeska, Thrice Reborn enters the battlefield with a loyalty counter on her for each time you've cast a commander from the command zone this game.

0: Choose target creature. Until your next turn, if that creature would deal combat damage to one of your opponents, it deals triple that damage to that player instead.

-X: Jeska, Thrice Reborn deals X damage to each of up to three targets.

Jeska, Thrice Reborn can be your commander.

Partner

({T}: Add {R}, {G}, or {W}.)

Jetmir's Garden enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

At the beginning of combat on your turn, creatures you control get +3/+3 and gain trample until end of turn.

{1}{G}: Until end of turn, target land you control becomes a 1/1 Elemental creature with vigilance, indestructible, and haste. It's still a land.

Partner (You can have two commanders if both have partner.)

As Katerina of Myra's Marvels enters the battlefield, choose a letter.

Whenever you cast a spell whose name begins with the chosen letter, create a white 2/2 Cat creature token with flying.

Partner (You can have two commanders if they both have partner.)

Whenever a commander you control deals combat damage to an opponent, it deals that much damage to each other opponent.

Partner (You can have two commanders if both have partner.)

Whenever a commander you control attacks, put a +1/+1 counter on it.

Partner (You can have two commanders if both have partner.)

{T}, Sacrifice three other artifacts and/or creatures: Look at the top three cards of your library. Put two of them into your hand and the other into your graveyard.

Partner (You can have two commanders if both have partner.)

Reach

Whenever another permanent enters the battlefield under your control, if it wasn't put onto the battlefield with this ability, you may put a permanent card with equal or lesser mana value from your hand onto the battlefield.

Partner (You can have two commanders if both have partner.)

Whenever you cast an instant or sorcery spell, flip a coin. If you lose the flip, return that spell to its owner's hand. If you win the flip, copy that spell, and you may choose new targets for the copy.

Partner (You can have two commanders if both have partner.)

Flying, haste

Whenever an opponent casts their second spell each turn, draw a card.

Partner (You can have two commanders if both have partner.)

{T}: Add {C} for each card you've drawn this turn.

Partner (You can have two commanders if both have partner.)

{1}{W}: Choose another target creature. Its controller may exile it with an aegis counter on it.

{2}{W}, {T}: Return all exiled cards with aegis counters on them to the battlefield under their owners' control.

Partner (You can have two commanders if both have partner.)

At the beginning of each player's end step, that player may draw a card if a player other than you lost life this turn.

Partner (You can have two commanders if both have partner.)

Flying

Whenever one or more Pirates you control deal damage to your opponents, you create a Treasure token for each opponent dealt damage. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Partner (You can have two commanders if both have partner.)

Whenever Miara, Thorn of the Glade or another Elf you control dies, you may pay {1} and 1 life. If you do, draw a card.

Partner (You can have two commanders if both have partner.)

Whenever a token you control leaves the battlefield, put a +1/+1 counter on Nadier, Agent of the Duskenel.

When Nadier leaves the battlefield, create a number of 1/1 green Elf Warrior creature tokens equal to its power.

Partner (You can have two commanders if both have partner.)

As Nocturno of Myra's Marvels enters the battlefield, choose a word with five or more letters.

Whenever you cast a spell with the chosen word in its rules text, you draw a card and you lose 2 life.

Partner (You can have two commanders if both have partner.)

At the beginning of combat on your turn, you may pay {X}{X}. When you do, distribute X +1/+1 counters among any number of target Elves.

Partner (You can have two commanders if both have partner.)

As long as it's your turn, creature tokens you control get +1/+4.

{3}{W}: Create a 1/1 white Soldier creature token.

Partner (You can have two commanders if both have partner.)

Flying

Tap another untapped creature you control with flying: Radiant, Serra Archangel gains protection from the color of your choice until end of turn.

Partner (You can have two commanders if both have partner.)

({T}: Add {W}, {U}, or {B}.)

Raffine's Tower enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

Flying

Other creatures you control get +1/+1.

At the beginning of your upkeep, you may return target creature card from your graveyard to your hand.

Partner (You can have two commanders if both have partner.)

Artifacts you control have protection from each mana value among artifacts you control.

Partner (You can have two commanders if both have partner.)

Reyhan, Last of the Abzan enters the battlefield with three +1/+1 counters on it.

Whenever a creature you control dies or is put into the command zone, if it had one or more +1/+1 counters on it, you may put that many +1/+1 counters on target creature.

Partner (You can have two commanders if both have partner.)

First strike, menace, trample

Partner (You can have two commanders if both have partner.)

You may have Sakashima of a Thousand Faces enter the battlefield as a copy of another creature you control, except it has Sakashima of a Thousand Faces's other abilities.

The "legend rule" doesn't apply to permanents you control.

Partner (You can have two commanders if both have partner.)

Flying

Whenever another creature dies, put two +1/+1 counters on Sengir, the Dark Baron.

Whenever another player loses the game, you gain life equal to that player's life total as the turn began.

Partner (You can have two commanders if both have partner.)

Flying

Whenever Siani, Eye of the Storm attacks, scry X, where X is the number of attacking creatures with flying.

Partner (You can have two commanders if both have partner.)

Flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.)

Creatures your opponents control without flying or reach can't block creatures with power 2 or less.

Partner (You can have two commanders if both have partner.)

Deathtouch

Whenever Silas Renn, Seeker Adept deals combat damage to a player, choose target artifact card in your graveyard. You may cast that card this turn.

Partner (You can have two commanders if both have partner.)

Slurrk, All-Ingesting enters the battlefield with five +1/+1 counters on it.

Whenever Slurrk or another creature you control dies, if it had a +1/+1 counter on it, put a +1/+1 counter on each creature you control that has a +1/+1 counter on it.

Partner (You can have two commanders if both have partner.)

({T}: Add {G}, {W}, or {U}.)

Spara's Headquarters enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

Trample

Whenever Tana, the Bloodsower deals combat damage to a player, create that many 1/1 green Saproling creature tokens.

Partner (You can have two commanders if both have partner.)

+2: Create two 0/1 black Thrull creature tokens.

+1: You may sacrifice another creature or planeswalker. If you do, draw two cards, then draw another card if the sacrificed permanent was a commander.

-10: Gain control of all commanders. Put all commanders from the command zone onto the battlefield under your control.

Tevesh Szat, Doom of Fools can be your commander.

Partner

If The Prismatic Piper is your commander, choose a color before the game begins. The Prismatic Piper is the chosen color.

Partner (You can have two commanders if both have partner.)

{4}: Scry 1, then reveal the top card of your library. If it's a land card, put it onto the battlefield tapped. Otherwise, draw a card.

Partner (You can have two commanders if both have partner.)

Landfall -- Whenever a land enters the battlefield under your control, create a colorless Equipment artifact token named Rock with "Equipped creature has '{1}, {T}, Sacrifice Rock: This creature deals 2 damage to any target'" and equip {1}.

Partner (You can have two commanders if both have partner.)

Whenever one or more cards leave your graveyard, create a tapped 2/2 black Zombie creature token.

Partner (You can have two commanders if both have partner.)

Lifelink

At the beginning of your postcombat main phase, you may pay X life, where X is the number of opponents that were dealt combat damage this turn. If you do, draw X cards.

Partner (You can have two commanders if both have partner.)

Whenever you cast your first spell each turn, choose an opponent at random. Vial Smasher the Fierce deals damage equal to that spell's mana value to that player or a planeswalker that player controls.

Partner (You can have two commanders if both have partner.)

({T}: Add {U}, {B}, or {R}.)

Xander's Lounge enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

Whenever another legendary permanent enters the battlefield under your control, put a +1/+1 counter on Yoshimaru, Ever Faithful.

Partner (You can have two commanders if both have partner.)

({T}: Add {B}, {R}, or {G}.)

Ziatora's Proving Ground enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)