It's Gwar v.s Gwar in this multiverse spanning graphic novel from Z2 Comics!

What can be more horrifying and terror-inducing than GWAR? The moment they must face the vomitous incarnations of themselves from a filthy alternate dimension! They've penetrated our world by rupturing the membrane which protected our very existence from these walking horrors. Unleashed in our universe, these dark mirror incarnations are bent on dominating and subjugating all of humanity to the will of The Master. Now... it is GWAR's throbbing, messy duty to save us all before it's too late!