Villians: Visser 3 (Animorphs) vs Anubus (Stargate) vs Darth Vader (Star Wars) vs Kahn (Star Trek) vs the Borg (Star Trek).
God-Like beings: The Ellimist/Crayak/Drode (Animorphs) vs the Ori (Stargate) vs
Q (Star Trek) vs the Primeval (Buffy the Vampire Slayer).
Ships: Visser 3's Blade ship (Animorphs) vs the Death Star (Star Wars) vs a Borg ship (Star Trek) vs a Shadow ship (Babylon 5).
Machines: The Chee (Animorphs) vs Star Wars droids vs Data (Star Trek).
Parasites: Yeerks (Animorphs) vs Go'uld (Star Gate) vs the Ceti eels Kahn used in Star Trek 2 vs the parasites in "ST:TNG Conspiracy".