Zameck Guildmage

{G}{U}: This turn, each creature you control enters with an additional +1/+1 counter on it.
{G}{U}, Remove a +1/+1 counter from a creature you control: Draw a card.

Brightflame

Radiance — Brightflame deals X damage to target creature and each other creature that shares a color with it. You gain life equal to the damage dealt this way.

Izzet Guildmage

({U/R} can be paid with either {U} or {R}.)
{2}{U}: Copy target instant spell you control with mana value 2 or less. You may choose new targets for the copy.
{2}{R}: Copy target sorcery spell you control with mana value 2 or less. You may choose new targets for the copy.

Duskmantle Guildmage

{1}{U}{B}: Whenever a card is put into an opponent's graveyard from anywhere this turn, that player loses 1 life.
{2}{U}{B}: Target player mills two cards.

Niv-Mizzet, Guildpact

Flying, hexproof from multicolored
Whenever Niv-Mizzet, Guildpact 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.

Bathe in Light

Radiance — Choose a color. Target creature and each other creature that shares a color with it gain protection from the chosen color until end of turn.

Boros Guildmage

{1}{R}: Target creature gains haste until end of turn.
{1}{W}: Target creature gains first strike until end of turn.

Surge of Zeal

Radiance — Target creature and each other creature that shares a color with it gain haste until end of turn.

Rally the Righteous

Radiance — Untap target creature and each other creature that shares a color with it. Those creatures get +2/+0 until end of turn.

Orzhov Guildmage

{2}{W}: Target player gains 1 life.
{2}{B}: Each player loses 1 life.

Incite Hysteria

Radiance — Until end of turn, target creature and each other creature that shares a color with it gain "This creature can't block."

Golgari Guildmage

{4}{B}, Sacrifice a creature: Return target creature card from your graveyard to your hand.
{4}{G}: Put a +1/+1 counter on target creature.

Gruul Guildmage

({R/G} can be paid with either {R} or {G}.)
{3}{R}, Sacrifice a land: Gruul Guildmage deals 2 damage to target player or planeswalker.
{3}{G}: Target creature gets +2/+2 until end of turn.

Skarrg Guildmage

{R}{G}: Creatures you control gain trample until end of turn.
{1}{R}{G}: Target land you control becomes a 4/4 Elemental creature until end of turn. It's still a land.

Senate Guildmage

{W}, {T}: You gain 2 life.
{U}, {T}: Draw a card, then discard a card.

Vizkopa Guildmage

{1}{W}{B}: Target creature gains lifelink until end of turn.
{1}{W}{B}: Whenever you gain life this turn, each opponent loses that much life.

Rakdos Guildmage

({B/R} can be paid with either {B} or {R}.)
{3}{B}, Discard a card: Target creature gets -2/-2 until end of turn.
{3}{R}: Create a 2/1 red Goblin creature token with haste. Exile it at the beginning of the next end step.

Niv-Mizzet Reborn

Flying
When Niv-Mizzet Reborn 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.

Nivix Guildmage

{1}{U}{R}: Draw a card, then discard a card.
{2}{U}{R}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Dimir Guildmage

({U/B} can be paid with either {U} or {B}.)
{3}{U}: Target player draws a card. Activate only as a sorcery.
{3}{B}: Target player discards a card. Activate only as a sorcery.

Conclave Guildmage

{G}, {T}: Creatures you control gain trample until end of turn.
{5}{W}, {T}: Create a 2/2 green and white Elf Knight creature token with vigilance.

Combine Guildmage

{1}{G}, {T}: This turn, each creature you control enters with an additional +1/+1 counter on it.
{1}{U}, {T}: Move a +1/+1 counter from target creature you control onto another target creature you control.

Selesnya Guildmage

{3}{G}: Create a 1/1 green Saproling creature token.
{3}{W}: Creatures you control get +1/+1 until end of turn.

Azorius Guildmage

{2}{W}: Tap target creature.
{2}{U}: Counter target activated ability. (Mana abilities can't be targeted.)

Simic Guildmage

({G/U} can be paid with either {G} or {U}.)
{1}{G}: Move a +1/+1 counter from target creature onto another target creature with the same controller.
{1}{U}: Attach target Aura attached to a permanent to another permanent with the same controller.

New Prahv Guildmage

{W}{U}: Target creature gains flying until end of turn.
{3}{W}{U}: Detain target nonland permanent an opponent controls. (Until your next turn, that permanent can't attack or block and its activated abilities can't be activated.)