Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Stone Rain

Firebreathing

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

Wheel of Fortune

Each player discards their hand, then draws seven cards.

Mox Ruby

Goblin Balloon Brigade

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

Howling Mine

At the beginning of each player's draw step, if Howling Mine is untapped, that player draws an additional card.

Black Lotus

{T}, Sacrifice Black Lotus: Add three mana of any one color.

Gauntlet of Might

Red creatures get +1/+1.
Whenever a Mountain is tapped for mana, its controller adds an additional {R}.

Goblin King

Other Goblins get +1/+1 and have mountainwalk.

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.

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.

Two-Headed Giant of Foriys

Trample
Two-Headed Giant of Foriys can block an additional creature each combat.

Rock Hydra

Rock Hydra enters with X +1/+1 counters on it.
For each 1 damage that would be dealt to Rock Hydra, if it has a +1/+1 counter on it, remove a +1/+1 counter from it and prevent that 1 damage.
{R}: Prevent the next 1 damage that would be dealt to Rock Hydra this turn.
{R}{R}{R}: Put a +1/+1 counter on Rock Hydra. Activate only during your upkeep.

Fork

Copy target instant or sorcery spell, except that the copy is red. You may choose new targets for the copy.

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.