Sphinx of the Final Word 
Creature — Sphinx
This spell can't be countered. Flying Hexproof (This creature can't be the target of spells or abilities your opponents control.) Instant and sorcery spells you control can't be countered.
Legality
standardLEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL