Jund Hackblade

As long as you control another multicolored permanent, this creature gets +1/+1 and has haste.

Dragon Arch

{2}, {T}: You may put a multicolored creature card from your hand onto the battlefield.

Maze Abomination

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Multicolored creatures you control have deathtouch.

Naya Hushblade

As long as you control another multicolored permanent, this creature gets +1/+1 and has shroud. (It can't be the target of spells or abilities.)

Bant Sureblade

As long as you control another multicolored permanent, this creature gets +1/+1 and has first strike.

Pillar of the Paruns

{T}: Add one mana of any color. Spend this mana only to cast a multicolored spell.

Widespread Thieving

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Whenever you cast a multicolored spell, create a Treasure token. Then you may pay {W}{U}{B}{R}{G}. If you do, you may play the exiled card without paying its mana cost.

Urza's Filter

Multicolored spells cost {2} less to cast.

Maze Glider

Flying
Multicolored creatures you control have flying.

Rienne, Angel of Rebirth

Flying
Other multicolored creatures you control get +1/+0.
Whenever another multicolored creature you control dies, return it to its owner's hand at the beginning of the next end step.

Ancient Cornucopia

Whenever you cast a spell that's one or more colors, you may gain 1 life for each of that spell's colors. Do this only once each turn.
{T}: Add one mana of any color.

Maze Rusher

Haste
Multicolored creatures you control have haste.

Niv-Mizzet Reborn

Flying
When Niv-Mizzet enters, reveal the top ten cards of your library. For each color pair, choose a card that's exactly those colors from among them. Put the chosen cards into your hand and the rest on the bottom of your library in a random order.

Grixis Grimblade

As long as you control another multicolored permanent, this creature gets +1/+1 and has deathtouch. (Any amount of damage it deals to a creature is enough to destroy that creature.)

Tome of the Guildpact

Whenever you cast a multicolored spell, draw a card.
{T}: Add one mana of any color.

General Ferrous Rokiric

Hexproof from monocolored
Whenever you cast a multicolored spell, create a 4/4 red and white Golem artifact creature token.

Hero of Precinct One

Whenever you cast a multicolored spell, create a 1/1 white Human creature token.

Maze Behemoth

Trample
Multicolored creatures you control have trample.

Niv-Mizzet, Guildpact

Flying, hexproof from multicolored
Whenever Niv-Mizzet deals combat damage to a player, it deals X damage to any target, target player draws X cards, and you gain X life, where X is the number of different color pairs among permanents you control that are exactly two colors.

The Mana Rig

Whenever you cast a multicolored spell, create a tapped Powerstone token. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")
{X}{X}{X}, {T}: Look at the top X cards of your library. Put up to two of them into your hand and the rest on the bottom of your library in a random order.

Vanishing Verse

Maze Sentinel

Vigilance
Multicolored creatures you control have vigilance.

Knight of New Alara

Each other multicolored creature you control gets +1/+1 for each of its colors.

Esper Stormblade

As long as you control another multicolored permanent, this creature gets +1/+1 and has flying.

Reborn Hope

Return target multicolored card from your graveyard to your hand.

Fallaji Wayfarer

Fallaji Wayfarer is all colors. This ability doesn't affect its color identity. (It can be in any deck whose commander's color identity includes green.)
Multicolored spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting a multicolored spell pays for {1} or one mana of a color that creature is.)

Vivid Revival

Return up to three target multicolored cards from your graveyard to your hand. Exile Vivid Revival.

Dragonfire Blade

Equipped creature gets +2/+2 and has hexproof from monocolored.
Equip {4}. This ability costs {1} less to activate for each color of the creature it targets.