Instant — Arcane, XUU (2)
Rare
You may exile a blue card with converted mana cost X from your hand rather than pay Disrupting Shoal's mana cost.
Counter target spell if its converted mana cost is X.
Illus. Scott M. Fischer

2/1/2005: Disrupting Shoal can target any spell, but does nothing unless that spell's converted mana cost is X.
Legal in Vintage (Type 1)
Legal in Legacy (Type 1.5)
Legal in Classic (MTGO)
Legal in Commander
Legal in Modern