All Rats have fear.
, Sacrifice a Rat: Create X 1/1 black Rat creature tokens, where X is the number of Rats you control.

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Uril gets +2/+2 for each Aura attached to it.

Whenever a creature dies, put a charge counter on this enchantment.
At the beginning of your first main phase, add for each charge counter on this enchantment.

When this creature enters, you gain 5 life.
When this creature leaves the battlefield, create a 3/3 green Beast creature token.

Whenever you attack, if it's the first combat phase of the turn, untap all attacking creatures. They gain first strike until end of turn. After this phase, there is an additional combat phase.
Choose a Background (You can have a Background as a second commander.)

Flash
Flying, vigilance
When Archangel Avacyn enters, creatures you control gain indestructible until end of turn.
When a non-Angel creature you control dies, transform Archangel Avacyn at the beginning of the next upkeep.

Whenever you gain life, target opponent loses that much life.

At the beginning of each player's draw step, that player draws an additional card.
Whenever an opponent draws a card, Nekusar deals 1 damage to that player.

Flying
Whenever Korvold enters or attacks, sacrifice another permanent.
Whenever you sacrifice a permanent, put a +1/+1 counter on Korvold and draw a card.

Ninjutsu (, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Higure deals combat damage to a player, you may search your library for a Ninja card, reveal it, put it into your hand, then shuffle.
: Target Ninja creature can't be blocked this turn.

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When this creature enters, destroy target artifact, enchantment, or land.

At the beginning of your upkeep, each opponent loses X life and you scry X, where X is the number of Zombies you control.
: Exile target creature card from a graveyard. Create a token that's a copy of it, except it's a 4/4 black Zombie.
When The Scarab God dies, return it to its owner's hand at the beginning of the next end step.

Whenever a creature an opponent controls dies, create a Treasure token. (It's an artifact with ", Sacrifice this token: Add one mana of any color.")
At the beginning of your upkeep, if you control ten or more Treasures, you win the game.

You draw X cards and you lose X life, where X is the mana value of a commander you own on the battlefield or in the command zone.

Whenever this creature attacks, defending player mills ten cards.

Haste
The Howling Abomination has trample as long as you've cast three or more spells this turn.
Whenever The Howling Abomination becomes the target of a spell, it gets +2/+2 until end of turn and deals 2 damage to each opponent.

Golden Rule — Whenever a token enters, you may have target player other than its controller create a token that's a copy of it, then you draw a card if an opponent created a token this way. Do this only once each turn.

Untap all permanents you control during each other player's untap step.

Flying
Iymrith has ward as long as it's untapped.
Whenever Iymrith deals combat damage to a player, draw a card. Then if you have fewer than three cards in hand, draw cards equal to the difference.

Flash
Double strike, vigilance, haste
Other creatures you control have haste.
, : Untap another target creature.

Whenever an opponent loses life, you gain that much life.

Whenever a Sliver deals combat damage to a player, its controller may draw a card.

Indestructible
As long as your devotion to green and white is less than seven, Karametra isn't a creature.
Whenever you cast a creature spell, you may search your library for a Forest or Plains card, put it onto the battlefield tapped, then shuffle.

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
: Skithiryx gains haste until end of turn.
: Regenerate Skithiryx.

Flying
Spells your opponents cast that target this creature cost an additional 3 life to cast.
Whenever another creature you control enters, this creature deals damage equal to that creature's power to any target.

Take an extra turn after this one.

( represents colorless mana.)
Trample, haste
Whenever this creature becomes the target of a spell an opponent controls, counter that spell unless its controller discards a card.

Flash
Lifelink
When this creature enters, exile up to one other target creature. That creature's controller gains life equal to its power.
Evoke—Exile a white card from your hand.

Indestructible
Whenever this creature is dealt damage, it deals that much damage to target opponent.
, : This creature fights another target creature.

Destroy all creatures with power greater than target creature's power.

Search your library for a card, put that card into your hand, then shuffle.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, add .

Creatures can't attack you or planeswalkers you control unless their controller pays for each of those creatures, where X is the number of enchantments you control.

Sliver creatures you control have indestructible. (Damage and effects that say "destroy" don't destroy them.)

+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

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

+2: Exile target permanent you own. Return it to the battlefield under your control at the beginning of the next end step.
−1: Creatures can't be blocked this turn.
−8: You get an emblem with "Whenever you cast a spell, exile target permanent."