Suddenly, all the haggling didn't seem so important.

Ravnica Remastered

Siege Wurm

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Trample

The List

Guilds of Ravnica

Magic 2015

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Trample (If this creature would assign enough damage to its blockers to destroy them, you may have it assign the rest of its damage to defending player or planeswalker.)

The Rubblefield was once among the wealthiest districts in Ravnica. All it took was a single wurm to reduce it to ruins.

Ravnica: City of Guilds

Convoke (Each creature you tap while playing this spell reduces its cost by {1} or by one mana of that creature's color.)
Trample