What are monsters?
Let’s move to some monsters and aliens. First let’s clarify what aliens and monsters are. They could be just like humans, arising out of evolution, as we know it. The Lovecraftian interpretation points towards the Ancient Aliens creators (that inspired the Alien universe too). While this is a juicy interpretation, the problem arises: why haven’t the other aliens made full contact with humans, or outright enslaved us? Basically, Fermi’s Paradox.
I devise several histories (ontologies) of what aliens and monsters are.
Remnants. Similar to the gods above, monsters and aliens are remnants of previous universes. Part of the initial expansion of the Universe, their primordial seed persevered and expanded into the new instantiation. Some are similar to humans (ex. Lizard-Men, Ghouls), some are very different (ex. Mi-go, Elder Things). Consequences: In previous universes, the aliens had different relationships with previous versions of humanity: alliances, wars, colonies. When they meet us again, this can cause troubles and confusions. There are parts of our ancestor memories that identify the aliens and monsters. The monsters and aliens have agendas and wills of their own, and are more akin to humans than the Cosmic Mourners.
Manifestations of the gods. The god-processes of the Universe create aliens and monsters — what we perceive as monsters and aliens. Their only will is as part of the god-processes.