Mystical Dispute 
Instant
This spell costs less to cast if it targets a blue spell.
Counter target spell unless its controller pays 
.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL
Instant
This spell costs less to cast if it targets a blue spell.
Counter target spell unless its controller pays .