As stupidly awesome as Killer Frost and Effigy are, I think Magneto and Klaw take this.
Klaw is immortal, he can make sound constructs strong enough to halt "Spikey Thing", fire off powreful blasts or use his power to disorient/deafen.
Magneto is.......Magneto 🙂
Killer Frost has nothing to work with here and I don't see Effigy posing a threat to either Klaw or Magneto.