@Damek35719 Here's a thread on aliens, non aliens, and partial aliens. If your sim is partial alien or other occult they have another trait that must be removed first. https://forums.thesims.com/en_us/discussion/comment/13890532/#Comment_13890532
Here's a guide to all cheats https://www.carls-sims-4-guide.com/cheats.php
Any other occult traits must be removed before you can add a new occult to the sim.
Ok so is there anything else that can mess with the add alien cheat to cover my basses. Also you've been very helpful I think I'm close to the answer it might be a trait my sim has
@Damek35719 If your sim is already a vampire, mermaid, or spellcaster they also can not become an alien.
If you remove all traits then re add them starting with alien trait first it might work, it worked for me in Nov.
I removed the alien trait because did not play nice with the vampire & spell caster traits, I kept turning purple.
Yep ancient bloodline trait thanks this is great for finding info and a nice community.
