A bounty hunter clad in bronze armor riveted crudely together to form a human-like figure. It was heavily armed, but the Rangers still overpowered it in their first battle.
A monster created by Cobalt with one of Polypton's Monsterification Bugs and a camera stolen from Sonny. It was destroyed by the Meso-Megazord.
A seven-foot skeleton, winged and clad in silver armor. He wielded a sword, which he could ignite when his eyes flashed orange. The Rangers destroyed him with their uncombined Zords.
An all-black humanoid with four arms and an insectlike face, green blood, and the ability to blend into shadows. He was able to steal the Rangers' morphers while they slept, and later fought a few on the ground. Belle, Tawny and Tori managed to destroy him with Cobalt's stolen sword and their bare hands, but returned to be destroyed again by the Meso-Megazord.
A Monsterification Bug augmented by Hades' Gilded Doom's runoff radiation. It was unintelligent, enormous and beetle-like, moving on spider-like legs, having clustered eyes, and bony plates that concealed envenomed quills which it could fire. It was destroyed by the Mesocannon.
A monster which resembled a rubbery, deformed skunk. It could blast a green asphyxiating gas, as its name implied, and was destroyed by the Rangers' Zords.
An enormous, silvery land-traveling squid that turned anyone it touched (including Kayla) into a metal statue. It was not intelligent and created by Polypton specifically to fight the Zords, but was destroyed by the Carno-Megazord.
The guardian of the Bloodstone, a giant (probably only animated by magic) spider made of rock. The Rangers shot it in the eyes with their Mesoblasters, making it explode.
Likely another bounty hunter, a creature clad in Viking armor set in charge of one group of scavengers after Northside's capture.
A red-and-bronze robot and a bounty hunter in charge of the makeshift hospital.
A praying mantis-like creature who apparently liked the taste of blood.
One of the guards overseeing a team of civilian scavengers, helped raid Mesozoic Manor.
An oil-based, oil-spewing creature who was destroyed by Kev in the Aquamarine Ranger suit, the first monster destroyed during the anarchic day after Mama D's death.
A collection of silvery blades and devices taken down by the Aquamarine, Pink and Yellow Rangers, and apparently one of Polypton's old creations.
An ice monster destroyed by Mary as the Yellow Ranger.
A vulture, one of the monster mob in the final fight before the Silverstar's arrival.
A limbed cobra whose fangs dripped venom.
A monster who wielded an assortment of grenades who was destroyed by Dwayne and Mary, hoist by his own petard.