Shatter the Sky

Each player who controls a creature with power 4 or greater draws a card. Then destroy all creatures.

Fumigate

Destroy all creatures. You gain 1 life for each creature destroyed this way.

Zurgo Helmsmasher

Haste
Zurgo Helmsmasher attacks each combat if able.
During your turn, Zurgo Helmsmasher has indestructible.
Whenever a creature dealt damage by Zurgo Helmsmasher this turn dies, put a +1/+1 counter on Zurgo Helmsmasher.

The Nipton Lottery

Choose a creature at random. You gain control of that creature until end of turn. Untap it. It gains haste until end of turn. Then destroy all other creatures.

No Witnesses

Each player who controls the most creatures investigates. Then destroy all creatures. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Depopulate

Each player who controls a multicolored creature draws a card. Then destroy all creatures.

Cleansing Nova

Choose one —
• Destroy all creatures.
• Destroy all artifacts and enchantments.