i am going to write a death metal song and waondering what type of scale to use.. any help would be appreciated.

What More Is There To Say..
natural minor, and harmonic minor work pretty well.

when you write death metal you dont really use scales as much as you just kind of go with the key, if that sometimes even.

just look up alot of early cannibal corpse, death or whatever you like the most, and see what they did.