Mountain

Silver Myr

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.

Alloy Myr

Skyreach Manta

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

Swamp

Leaden Myr

Island

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.

Plains

Suntouched Myr

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

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.

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.

Forest

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Gold Myr

Iron Myr

Urza's Mine

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

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.

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.)

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.

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.

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.