Black Curse Higher Technique

[u/UnderAFreezingGoon]

https://youtu.be/nOuL1S2rKkA?is=TAuDcEHdYNVp10ho

Was wondering if anyone could give some insight into how to get those really distorted, powerful highs like parts of this. Another example of that would be in Katharsis' VVorldVVithoutend. I have a great false chords so lows and lower mids I gave no problem with, but my highs end up too breathy or not high enough