What subgenre of metal is "To Mega Therion" by Celtic Frost?
 

In your opinion what is a primary subgenre of metal for this album?

This album is considered a significant influence on black and death metal and it's even labeled as black metal by some Internet pages but to me it doesn't sound like black metal musically or vocally.
I'd say it's a hybrid metal album, primarily thrash metal with some doom and heavy metal stuff.

What would you say?

Asking people to debate about which subgenre a metal band is should be a war crime. That said I'll listen to it and try to give you my best guess.

Motorhead-core