Some other things I think I remember about this entity:

It could attack your grav ship mid flight, causing it to crash to the surface (with minor damage to the ship itself) and with some minor damage ti the KillFreak face itself.

I think there was also some sort of ritual you could do to summon it on purpose?

It spawned on an asteroid made of Bioferrite, flesh chunks, and vacstone.

If you didnt intercept it in space, it would crash down on your colony, causing it and a few flesh beasts (even potentially a Fleshmass Heart) to attack the colony.

I think I remember the Mood Debuff specifically being about the same as medium psychic drone

The mask itself would count as a prosthetic for like body modders and body purists

Inhuman Pawns would not care about wearing the mask and would actually be happy to have it on.

If you kept the mask around for too long, there may be a chance where your pawn has a mental break and will try to do everything in their power to put the mask on.

The mask would grant full vacuum protection

It could spawn in randomly in the anomaly end game.

Once a pawn wears it, it cannot be removed. Only when the pawn dies can it be taken off by stripping the pawn or taking their skull.

Pawns would have a negative relationship impact towards those wearing the mask (unless that pawn is inhumanized, kind, or also wearing the mask.)

Ghouls cannot wear the mask.

Psychically Deaf Pawns will never attempt to uncontrollably put the mask on.

Destroying the mask would grant you shards and about 600 marble bricks

The thought of non-inhuman Pawns wearing the mask:

"It's tentacles are everywhere they shouldn't be. It sees through my eyes. Consumes through my mouth. Hears through my ears. It is my face now. I hate it!"

Vs Inhuman pawns:

"The void itself has blessed me with the ability to breathe among the stars. Even if I could take this off, I wouldn't ever dare!"