Logic Knot 
Instant
Delve (Each card you exile from your graveyard while casting this spell pays for 
.)
Counter target spell unless its controller pays .
Legality
standardNOT LEGALpioneerNOT LEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL
Instant
Delve (Each card you exile from your graveyard while casting this spell pays for .)
Counter target spell unless its controller pays .