Specific drop mechanics, eg. amunamu void

I heared in some youtube video that GGG confirmed that drop difference between defeating rare mob with amunamu void modifier in his void or outside of the void is intendent mechanic and there are more of them.
Does anyone know some other drop mechanics of this kind?
I play SSF, so if there are other drop mechanic (even not abyss related) it would be great to know.
For example, right now I need omen of blackblooded for kurgal suffix and I wonder if there is some method to target this omen. At this point I know only amanamu void as guaranteed specific abyss omen farming method, and other abyss omens are soooo rare.

It's the only one I've heard of so far. The are other interactions but no one has publicly discovered then yet afaik.

Do you know what video it was? You sure there are more strats like amunamu void?

@ryszek I saw it here:
https://youtu.be/-c7ykBa4ovw?si=Kl8-2vFcoLIWU6kz&t=224

When I play SSF I don't ultra farm single machanic. I farm it until I get most needed item for me right now and move to next one.
I dropped already over 20 echos but omen of blackblooded (kurgal modifier) dropped once, somewhere in the beggining of my mapping, when I even didn't know about that void thing. Seeing how big a difference this drop machanic really is, it would be useful to know more stuff like that so you wouldn't have to spend 2 weeks farming single mechanic in SSF.

@Edit: I see link to specific second of the clip looks weird so if you prefer, here is the full video, and the timestamp is ~3:45
https://www.youtube.com/watch?v=-c7ykBa4ovw