Undertone/Overtone Singing and Deep Throat Chanting

if you are a fan of The HU, Heilung, Abbath, or Popeye the sailor, you've likely heard this style of vocals. I'm gonna do my personal best to convey my techniques for obtaining this technique and making it your own.
Songs used are:
A City of the Murdered (unreleased at time of this video)
Darkroot (inspired by the area of the same name in Dark Souls).

[@gageclark2390]

I figured out this technique myself I believe it’s called subharmonic singing