What instruments are used in the song Monster by Skillet?

* Guitars: 7-string guitars (tuned A-G-C-F-A-D-G)

* Bass: 5-string bass (tuned B-E-A-D-G)

* Drums: A standard drum kit with double bass pedals

* Keyboards: Synths, samplers, and pianos.

* Vocals: Harsh vocals performed by John Cooper, clean vocals performed by Korey Cooper and Jen Ledger.