Spectral Denial - Tarkir: Dragonstorm - 58

Instant

Mana Cost: {X}{U}

This spell costs {1} less to cast for each creature you control with power 4 or greater.
Counter target spell unless its controller pays {X}.

Uncommon · Tarkir: Dragonstorm · #58 (TDM)

Illustrated by Xabi Gaztelua