Siege Wurm

Creature - Wurm 5/5, 5GG (7)
Convoke (Each creature you tap while casting this spell reduces its cost by {1} or by one mana of that creature's color.)

Trample¹
The Rubblefield was once among the wealthiest districts in Ravnica. All it took was a single wurm to reduce it to ruins.
Illus. Carl Critchlow

Format Legality	Legal in Vintage, Legacy, Extended, MTGO Classic Banned in Standard
Printings (1/9)	Ravnica: City of Guilds (Common)