Roots Search: Shokushin Buttai X

Both are old and fairly obscure sci-fi horror where the alien is some sort of god-like entity that uses psychic powers to torment and kill its victims one by one, making for some entertainingly strange scenes,as well as having an odd but interesting musical score. 

Both are sci-fi horror which take place in a spaceship throughout,as well as have an entire cast of visually diverse and fun looking characters,all though Roots search is far more silly and poorly executed than Lily C.A.T. both can still be watched back to back fairly well.