Lavaball Trap

Cascade, cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order. Then do it again.)

Call Forth the Tempest deals damage to each creature your opponents control equal to the total mana value of other spells you've cast this turn.

As an additional cost to cast this spell, reveal a creature card from your hand.

Disaster Radius deals X damage to each creature your opponents control, where X is the revealed card's mana value.

Target creature an opponent controls deals damage equal to its power to each other creature that player controls, then each of those creatures deals damage equal to its power to that creature.

Undaunted (This spell costs less to cast for each opponent.)

Exile two target creatures. For each of those creatures, its controller reveals cards from the top of their library until they reveal a creature card, puts that card onto the battlefield, then shuffles the rest into their library.

This spell costs less to cast for each creature on the battlefield.

Blasphemous Act deals 13 damage to each creature.

Return target instant or sorcery card from your graveyard to your hand. Volcanic Vision deals damage equal to that card's mana value to each creature your opponents control. Exile Volcanic Vision.