Golgari Signet

Composite Golem

Sacrifice Composite Golem: Add {W}{U}{B}{R}{G}.

Orzhov Signet

Pentad Prism

Sunburst (This enters with a charge counter on it for each color of mana spent to cast it.)
Remove a charge counter from Pentad Prism: Add one mana of any color.

Woodland Wanderer

Vigilance, trample
Converge — Woodland Wanderer enters with a +1/+1 counter on it for each color of mana spent to cast it.

Engineered Explosives

Sunburst (This enters with a charge counter on it for each color of mana spent to cast it.)
{2}, Sacrifice Engineered Explosives: Destroy each nonland permanent with mana value equal to the number of charge counters on Engineered Explosives.

Etched Oracle

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
{1}, Remove four +1/+1 counters from Etched Oracle: Target player draws three cards.

Sweep the Skies

Converge — Create a 1/1 colorless Thopter artifact creature token with flying for each color of mana spent to cast this spell.

Heliophial

Sunburst (This enters with a charge counter on it for each color of mana spent to cast it.)
{2}, Sacrifice Heliophial: It deals damage equal to the number of charge counters on it to any target.

Urtet, Remnant of Memnarch

Whenever you cast a Myr spell, create a 1/1 colorless Myr artifact creature token.
At the beginning of combat on your turn, untap each Myr you control.
{W}{U}{B}{R}{G}, {T}: Put three +1/+1 counters on each Myr you control. Activate only during your turn.

Glinting Creeper

Converge — Glinting Creeper enters with two +1/+1 counters on it for each color of mana spent to cast it.
Glinting Creeper can't be blocked by creatures with power 2 or less.

Simic Signet

Bring to Light

Converge — Search your library for a creature, instant, or sorcery card with mana value less than or equal to the number of colors of mana spent to cast this spell, exile that card, then shuffle. You may cast that card without paying its mana cost.

Tajuru Stalwart

Converge — Tajuru Stalwart enters with a +1/+1 counter on it for each color of mana spent to cast it.

Iron Myr

Spinal Parasite

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
Remove two +1/+1 counters from Spinal Parasite: Remove a counter from target permanent.

Suncrusher

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
{4}, {T}, Remove a +1/+1 counter from Suncrusher: Destroy target creature.
{2}, Remove a +1/+1 counter from Suncrusher: Return Suncrusher to its owner's hand.

Crystalline Crawler

Converge — Crystalline Crawler enters with a +1/+1 counter on it for each color of mana spent to cast it.
Remove a +1/+1 counter from Crystalline Crawler: Add one mana of any color.
{T}: Put a +1/+1 counter on Crystalline Crawler.

Fist of Suns

You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Exert Influence

Converge — Gain control of target creature if its power is less than or equal to the number of colors of mana spent to cast this spell.

Unified Front

Converge — Create a 1/1 white Kor Ally creature token for each color of mana spent to cast this spell.

Jenson Carthalion, Druid Exile

Whenever you cast a multicolored spell, scry 1. If that spell was all colors, create a 4/4 white Angel creature token with flying and vigilance.
{5}, {T}: Add {W}{U}{B}{R}{G}.

Prism Array

Converge — Prism Array enters with a crystal counter on it for each color of mana spent to cast it.
Remove a crystal counter from Prism Array: Tap target creature.
{W}{U}{B}{R}{G}: Scry 3.

Radiant Epicure

Converge — When Radiant Epicure enters, each opponent loses X life and you gain X life, where X is the number of colors of mana spent to cast this spell.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Arcbound Wanderer

Modular—Sunburst (This creature enters with a +1/+1 counter on it for each color of mana spent to cast it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Copper Myr

Etched Monstrosity

Etched Monstrosity enters with five -1/-1 counters on it.
{W}{U}{B}{R}{G}, Remove five -1/-1 counters from Etched Monstrosity: Target player draws three cards.

Alloy Myr

Lunar Avenger

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
Remove a +1/+1 counter from Lunar Avenger: Lunar Avenger gains your choice of flying, first strike, or haste until end of turn.

Suntouched Myr

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)

Silver Myr

Legacy Weapon

{W}{U}{B}{R}{G}: Exile target permanent.
If Legacy Weapon would be put into a graveyard from anywhere, reveal Legacy Weapon and shuffle it into its owner's library instead.

Azorius Signet

Lux Artillery

Whenever you cast an artifact creature spell, it gains sunburst. (It enters with a +1/+1 counter on it for each color of mana spent to cast it.)
At the beginning of your end step, if there are thirty or more counters among artifacts and creatures you control, Lux Artillery deals 10 damage to each opponent.

Boros Signet

Prismatic Ending

Converge — Exile target nonland permanent if its mana value is less than or equal to the number of colors of mana spent to cast this spell.

Skyreach Manta

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
Flying

Channel the Suns

Jegantha, the Wellspring

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 {3} as a sorcery.)
{T}: Add {W}{U}{B}{R}{G}. This mana can't be spent to pay generic mana costs.

Timeless Lotus

Timeless Lotus enters tapped.
{T}: Add {W}{U}{B}{R}{G}.

Infuse with the Elements

Converge — Put X +1/+1 counters on target creature, where X is the number of colors of mana spent to cast this spell. That creature gains trample until end of turn.

Kaleidostone

When Kaleidostone enters, draw a card.
{5}, {T}, Sacrifice Kaleidostone: Add {W}{U}{B}{R}{G}.

Sol Ring

Jodah, Archmage Eternal

Flying
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Izzet Signet

Roilmage's Trick

Converge — Creatures your opponents control get -X/-0 until end of turn, where X is the number of colors of mana spent to cast this spell.
Draw a card.

Gold Myr

Kaleidoscorch

Converge — Kaleidoscorch deals X damage to any target, where X is the number of colors of mana spent to cast this spell.
Flashback {4}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Dimir Signet

Crystal Quarry

{T}: Add {C}.
{5}, {T}: Add {W}{U}{B}{R}{G}.

Sawtooth Thresher

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
Remove two +1/+1 counters from Sawtooth Thresher: Sawtooth Thresher gets +4/+4 until end of turn.

Gruul Signet

Clearwater Goblet

Sunburst (This enters with a charge counter on it for each color of mana spent to cast it.)
At the beginning of your upkeep, you may gain life equal to the number of charge counters on Clearwater Goblet.

Selesnya Signet

Rakdos Signet

Skyrider Elf

Flying
Converge — Skyrider Elf enters with a +1/+1 counter on it for each color of mana spent to cast it.

Baton of Courage

Flash
Sunburst (This enters with a charge counter on it for each color of mana spent to cast it.)
Remove a charge counter from Baton of Courage: Target creature gets +1/+1 until end of turn.

Brilliant Spectrum

Converge — Draw X cards, where X is the number of colors of mana spent to cast this spell. Then discard two cards.

Courier's Briefcase

When Courier's Briefcase enters, create a 1/1 green and white Citizen creature token.
{T}, Sacrifice Courier's Briefcase: Add one mana of any color.
{W}{U}{B}{R}{G}, {T}, Sacrifice Courier's Briefcase: Draw three cards.

Opaline Bracers

Sunburst (This enters with a charge counter on it for each color of mana spent to cast it.)
Equipped creature gets +X/+X, where X is the number of charge counters on Opaline Bracers.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Chamber Sentry

Chamber Sentry enters with a +1/+1 counter on it for each color of mana spent to cast it.
{X}, {T}, Remove X +1/+1 counters from Chamber Sentry: It deals X damage to any target.
{W}{U}{B}{R}{G}: Return Chamber Sentry from your graveyard to your hand.

Solarion

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
{T}: Double the number of +1/+1 counters on Solarion.

Radiant Flames

Converge — Radiant Flames deals X damage to each creature, where X is the number of colors of mana spent to cast this spell.

Painful Truths

Converge — You draw X cards and you lose X life, where X is the number of colors of mana spent to cast this spell.

Leaden Myr

Ramos, Dragon Engine

Flying
Whenever you cast a spell, put a +1/+1 counter on Ramos for each of that spell's colors.
Remove five +1/+1 counters from Ramos: Add {W}{W}{U}{U}{B}{B}{R}{R}{G}{G}. Activate only once each turn.

Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon, the Boundless enters, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.