Storm World

At the beginning of each player's upkeep, this enchantment deals X damage to that player, where X is 4 minus the number of cards in their hand.

Channel

Until end of turn, any time you could activate a mana ability, you may pay 1 life. If you do, add {C}.

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.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Taiga

Wheel of Fortune

Each player discards their hand, then draws seven cards.

Mountain

Jayemdae Tome

Fork

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

Regrowth

Return target card from your graveyard to your hand.

Mana Clash

You and target opponent each flip a coin. Mana Clash deals 1 damage to each player whose coin comes up tails. Repeat this process until both players' coins come up heads on the same flip.

The Rack

As this artifact enters, choose an opponent.
At the beginning of the chosen player's upkeep, this artifact deals X damage to that player, where X is 3 minus the number of cards in their hand.

Chain Lightning

Chain Lightning deals 3 damage to any target. Then that player or that permanent's controller may pay {R}{R}. If the player does, they may copy this spell and may choose a new target for that copy.

Storm Seeker

Storm Seeker deals damage to target player equal to the number of cards in that player's hand.