|This article is about a/an group of villains in Power Rangers Mystic Force.|
|Generals and other Notable Members:||Megahorn, Black Lance, Magma, Oculous, Hekatoid, Itassis, Serpentina, Gekkor, Matoombo|
The Ten Terrors of the Underworld are ten god-like demons/monsters and the most powerful servants of Octomus.
They supposedly only existed in the worst of nightmares but were discovered by Necrolai, dwelling in the Lower Sanctum of the Underworld. They are all normally giant in size, especially in their lair but they can change their size at will to match the height of the Rangers. They are adamant about upholding the Laws of Darkness and are willing to kill each other (and be killed) for transgressing them; it appears that if they don't follow the Rules, there will be dire consequences for them and they may be banished. Their cardinal law is that those who oppose dark magic are to be punished (and then punished and punished some more). They appeared on Earth to demonstrate their power and announce themselves, and easily decimated the Manticore Megazord.
In their lair stands a giant stone monolith known as the Stone of Judgement which projects a ball of light that passes over the Ten Terrors, stopping on the weapon of whoever is chosen to punish Earth next. They waited for Octomus' return, but after the destruction of Imperious emerged to challenge the Mystic Rangers in search of The Light, the one being who could thwart the Master's plans.
After being discovered in the Underworld by Necrolai, the Terrors appeared on the surface to announce their arrival to the world. Afterwards, Magma was chosen to attack the surface world. He engaged the Rangers in a series of fierce battles, lighting a nearby tower on fire and boasting that he would destroy them before it burnt out. Despite his great power, the Rangers managed to survive longer than the fire, and Sculpin executed Magma in keeping with the Rules of Darkness. Oculous was then dispatched to battle the Rangers, but was defeated by Nick using Fire Heart as a Battlizer. Serpentina was chosen next and quickly fell, with Megahorn being the fourth to be chosen. Black Lance was sent to assist him in battle, but was dragged back into the underworld by the Centaurus Megazord. The combined efforts of the Manticore Megazord and Solar Streak proved too much for Megahorn alone, and he was destroyed as well.
Hekatoid, the fifth terror, proved surprisingly effective, capturing Udonna and holding her Snow Staff as well. However, when Udonna was rescued and recovered her Snow Staff and White Ranger powers, she and the other five Rangers put a swift end to Hekatoid. Despite this loss, however, the remaining terrors managed to locate Leanbow, the warrior who had defeated the Master and had imprisoned him in his own body. They successfully defeated Leanbow and retrieved the Master's Soul, though Gekkor perished in battle with Leanbow shortly thereafter. Matoombo was then chosen to attack the surface, but proved to have a gentle heart more interested in learning about humans than fighting them. Unfortunately, he was then selected as the Master's vessel, and despite efforts by the Rangers to take him to safety, he was captured and forced to serve as the Master's host.
Itassis was then chosen by the Master to fight the Rangers, but proved unwilling to follow the Master's orders any longer. As such, she was defeated by Black Lance and Sculpin, but subsequently revived by a similarly repentant Necrolai. She later battled Sculpin and destroyed him, while Black Lance fell to Rangers. Itassis also helped the Rangers in their final battle with the Master, which left her free to learn more about honor from Daggeron while a restored Matoombo came to enjoy a new life of peace.
- Sculpin (deceased)
- Magma (deceased)
- Oculous (deceased)
- Megahorn (deceased)
- Hekatoid (deceased)
- Serpentina (deceased)
- Gekkor (deceased)
- Black Lance (deceased)