Rime Chill

Vivid — This spell costs {1} less to cast for each color among permanents you control.
Tap up to two target creatures. Put a stun counter on each of them. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Draw a card.

Luminollusk

Deathtouch
Vivid — When this creature enters, you gain life equal to the number of colors among permanents you control.

Ioreth of the Healing House

{T}: Untap another target permanent.
{T}: Untap two other target legendary creatures.

Glister Bairn

Vivid — At the beginning of combat on your turn, another target creature you control gets +X/+X until end of turn, where X is the number of colors among permanents you control.

Prismabasher

Trample
Vivid — When this creature enters, up to X target creatures you control get +X/+X until end of turn, where X is the number of colors among permanents you control.

Distorting Lens

{T}: Target permanent becomes the color of your choice until end of turn.

Aurora Awakener

Trample
Vivid — When this creature enters, reveal cards from the top of your library until you reveal X permanent cards, where X is the number of colors among permanents you control. Put any number of those permanent cards onto the battlefield, then put the rest of the revealed cards on the bottom of your library in a random order.

Conqueror's Flail

Equipped creature gets +1/+1 for each color among permanents you control.
As long as this Equipment is attached to a creature, your opponents can't cast spells during your turn.
Equip {2}

Murkfiend Liege

Other green creatures you control get +1/+1.
Other blue creatures you control get +1/+1.
Untap all green and/or blue creatures you control during each other player's untap step.

Prismatic Undercurrents

Vivid — When this enchantment enters, search your library for up to X basic land cards, where X is the number of colors among permanents you control. Reveal those cards, put them into your hand, then shuffle.
You may play an additional land on each of your turns.

Marvin, Murderous Mimic

Marvin has all activated abilities of creatures you control that don't have the same name as this creature.

Shinestriker

Flying
Vivid — When this creature enters, draw cards equal to the number of colors among permanents you control.

Chromatic Orrery

You may spend mana as though it were mana of any color.
{T}: Add {C}{C}{C}{C}{C}.
{5}, {T}: Draw a card for each color among permanents you control.

Mondo Gecko

{1}, Discard a card: Until end of turn, Mondo Gecko becomes the color of your choice and gains hexproof from that color.
Whenever Mondo Gecko deals combat damage to a player, draw a card for each color among permanents you control.

Wildvine Pummeler

Vivid — This spell costs {1} less to cast for each color among permanents you control.
Reach, trample

Case of the Shattered Pact

When this Case enters, search your library for a basic land card, reveal it, put it into your hand, then shuffle.
To solve — There are five colors among permanents you control. (If unsolved, solve at the beginning of your end step.)
Solved — At the beginning of combat on your turn, target creature you control gains flying, double strike, and vigilance until end of turn.

Tam, Mindful First-Year

Each other creature you control has hexproof from each of its colors.
{T}: Target creature you control becomes all colors until end of turn.

Scion of Draco

Domain — This spell costs {2} less to cast for each basic land type among lands you control.
Flying
Each creature you control has vigilance if it's white, hexproof if it's blue, lifelink if it's black, first strike if it's red, and trample if it's green.

Bloom Tender

Vivid — {T}: For each color among permanents you control, add one mana of that color.