Well playing some single note scale ideas will work. Of course synchronizing your picking with the blast beat or trem picking stuff. Listen to some Deeds of flesh or Spawn of Posession or other bands in general for their blast beats and what the guitar players are doing over them to get a general idea.
Here is a list of bands to check out.

Disgorge
Deeds Of Flesh
Origin
Necrophagist
Suffocation
The Faceless
Decrepit Birth

Listen to all kinds of different death metal bands and try to listen what the guitar players are doing over the blast.

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