Name:Thassa's Rebuff
ManaCost:1 U
Types:Instant
A:SP$ Counter | Cost$ 1 U | TargetType$ Spell | TgtPrompt$ Select target spell | ValidTgts$ Card | UnlessCost$ X | References$ X | SpellDescription$ Counter target spell unless its controller pays {X}, where X is your devotion to blue.
SVar:X:Count$Devotion.Blue
SVar:Picture:http://www.wizards.com/global/images/magic/general/thassas_rebuff.jpg
Oracle:Counter target spell unless its controller pays {X}, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)