Impending Disaster

At the beginning of your upkeep, if there are seven or more lands on the battlefield, sacrifice Impending Disaster and destroy all lands.

Sol Ring

Wildfire

Each player sacrifices four lands of their choice. Wildfire deals 4 damage to each creature.

Bust

Boom

Destroy target land you control and target land you don't control.

Boom // Bust

Thoughts of Ruin

Each player sacrifices a land of their choice for each card in your hand.

Svella, Ice Shaper

{3}, {T}: Create a colorless snow artifact token named Icy Manalith with "{T}: Add one mana of any color."
{6}{R}{G}, {T}: Look at the top four cards of your library. You may cast a spell from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.