Chord of Calling - Ravnica: City of Guilds - 156

Instant

Mana Cost: {X}{G}{G}{G}

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.)
Search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

Rare · Ravnica: City of Guilds · #156 (RAV)

Illustrated by Heather Hudson