Raise the Palisade

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Nuclear Fallout

Each creature gets twice -X/-X until end of turn. Each player gets X rad counters.

River's Rebuke

Return all nonland permanents target player controls to their owner's hand.

The Meathook Massacre

When The Meathook Massacre enters, each creature gets -X/-X until end of turn.
Whenever a creature you control dies, each opponent loses 1 life.
Whenever a creature an opponent controls dies, you gain 1 life.

Aetherize

Return all attacking creatures to their owner's hand.

Deadly Tempest

Destroy all creatures. Each player loses life equal to the number of creatures they controlled that were destroyed this way.

Perish

Destroy all green creatures. They can't be regenerated.

Kotis, the Fangkeeper

Indestructible
Whenever Kotis deals combat damage to a player, exile the top X cards of their library, where X is the amount of damage dealt. You may cast any number of spells with mana value X or less from among them without paying their mana costs.

Forest

Culling Ritual

Destroy each nonland permanent with mana value 2 or less. Add {B} or {G} for each permanent destroyed this way.

Desynchronization

Return each nonland permanent that's not historic to its owner's hand. (Artifacts, legendaries, and Sagas are historic.)

Kindred Dominance

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Nature's Ruin

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Virtue's Ruin

Extinguish All Hope

Reach the Horizon

Search your library for up to two basic land cards and/or Town cards with different names, put them onto the battlefield tapped, then shuffle.

Blood Money

Destroy all creatures. For each nontoken creature destroyed this way, you create a tapped Treasure token.

Mutilate

All creatures get -1/-1 until end of turn for each Swamp you control.

Blood on the Snow

Choose one —
• Destroy all creatures.
• Destroy all planeswalkers.
Then return a creature or planeswalker card with mana value X or less from your graveyard to the battlefield, where X is the amount of {S} spent to cast this spell. ({S} is mana from a snow source.)

Exude Toxin

Each non-Dragon creature gets -X/-X until end of turn. (Then shuffle this card into its owner's library.)

Scavenger Regent

Scavenger Regent // Exude Toxin

Swamp

Aetherspouts

For each attacking creature, its owner puts it on their choice of the top or bottom of their library.