Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Brass Man

Brass Man doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {1}. If you do, untap Brass Man.

Goblin Balloon Brigade

{R}: Goblin Balloon Brigade gains flying until end of turn.

Disintegrate

Disintegrate deals X damage to any target. If it's a creature, it can't be regenerated this turn, and if it would die this turn, exile it instead.

Mountain

Granite Gargoyle

Flying
{R}: Granite Gargoyle gets +0/+1 until end of turn.

Power Surge

At the beginning of each player's upkeep, Power Surge deals X damage to that player, where X is the number of untapped lands they controlled at the beginning of this turn.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Firebreathing

Enchant creature
{R}: Enchanted creature gets +1/+0 until end of turn.

Atog

Sacrifice an artifact: Atog gets +2/+2 until end of turn.