Boma

Boma are cryptids of Native Americans of the Pacific Northwest and California [Not IRL] that were defeated by five braves of each of the tribes around what became Battle Mountain, California 5,000 years ago. They were sealed away with Raven's help. After that day though, Raven said he would return when the seal was broken to track down five new braves to restore justice to the land.

It is believed Jezella regenerated into Raven and selected the Nitro Rangers to continue the quest, which lead to the reunification of the Geauga Society.

Darlo
Darlo is a Boma with a car themed cryptid that started the Rangers on a street chase up I-15 that ended with a Megazord Fight in Las Vegas. He was soon followed by an army of White Walkers and the Phantom Rangers, which caused another chase with the Dark Walker.

Frail Golbin
Frail Goblin is a witch themed Boma who was ordered by Bella and Jackson to help surround the Nitro Rangers and prevent them from (as found out after the fact) getting to Kings Island to stop Beast's execution.

After an initial scuffle, the rangers were able to pass before getting surrounded. The fighting continued when they arrived at Cedar Point/Frontier Town.

She is eventually done in by the Nitro Rangers. First by Nitro Cannon, then Nitro Megazord. At the same time, the Wild West Rangers booted up Battalion Robo for the first time and fought Vengeance Megazord.

Arsenal
She can expel toxic gas which turns mortal vulnerable, but has no effect on the ARC's.

Executioner Boma
Executioner Boma is the equivalent of the Grim Reaper created by Ta'xet that had gone rouge. Its ancient appearance was a red shadow with a scythe, but now resembles a walking house.

He was order to execute Bert/The Beast by Bella. The other ARC's at Kings Island had fallen into a panic, which was solved when Firehawk and Beast unlocked the Red and Yellow Jet Souls respectively and helped their Coaster Force comrades, Gatekeeper, Raptor, and WildCat in fighting him. He however disappeared as Peter and Bella had a one on one Megazord Fight.

He was one of the few Boma to appear in the Boma Army during the final battle of the Coaster War where all the ARC's came together to insure the final defeat of The Boma

Arsenal
He is equipped with a scythe.

The Chiller
The Chiller is the Boma's equivalent of Gashadokuro. He put a winter wonderland hex on Canada's Wonderland in hopes of incasing their ARC's in ice, leaving the park closed until the issue could be solved.

After a brief duel with Valravn/Raven Knight, the rangers soon notice the park beginning to thaw and soon get Borris/Behemoth, Lizzie/Leviathan, and Ezra/Ziz equipped as Coaster Force Crimson (III), Coaster Force Teal, and Coaster Force Brown respectively.

He is regrown and defeated by Nitro Ultrazord. Shortly after, we are introduced to a new zord series, the Legend Beasts.

Arsenal
He is equipped with a staff that can preform Ice Magic, as he was often blamed for when it got freezing in the Pacific North West as it normally does get to negative Centigrade.

Scarowind
Scarowind is a garden themed Boma that might be an Executioner, although this is not confirmed. He was able to get Hurler, Intimidator, Carolina Cyclone, Ricochet, Vortex, and Flying Cobra (one of the original members of the Geauga Society) under his control.

They fought the Coaster Force Rangers, along with Afterburn, Gemini, and the bonded pairs of roller coasters. He was defeated by the Coaster Cannon before being defeated by Top Gun Megazord.

Arsenal
It is inferred that he is an executioner because he has a  scythe. He may have simple Boma spell powers as he was able to get about half of Carowinds ARC's in his control (as The Thunder Road boys were believed to have been dismantled and it is believed Villain became [TBC])

Vengeance Eater
Vengeance Easter was a Boma creature created by Blakcjack, Chess, and Wyatt when they unearthed the Great Bear Zord. It stole the color from the Nitro Rangers. McCormick/Corkscrew finally gets to transform as Coaster Force Navy and chased the monster. They soon end up wrinkling to Kings Dominion, where she works with the Wild West Coasters and Twisted Timbers to defeat it.

When he expels the Nitro Powers, each of the core Wild West Coasters takes the Zord they had used at Christmas (But Kate and McCormick join in the Megazord) and end his sentience.

Arsenal
He can become Drill like, which can disturb the ground, and apparently the fabric of the universe

Galotar
Galotar was the former general of The Boma Tribes long ago, but fled from the braves in hopes of his life being spared. However, a sixth (female) brave from the plains (one of Lola's ancestors) was able to banish him back to the Underlands (which was not confirmed where they originated til he debuted).

He was resurrected the same time as the others, but Bella's place prevented The Boma from killing him for being a deserter and was proclaimed an Assassin, which was the level beneath her and the Vengeance Rangers themselves.

He was another Cold Weather Boma, but was more known for appearing before poor tidings that could bring the end of whole groups.

He went to attack Michigan's Adventure during the ARC's wood carving festival. The force of the rangers turned any reaming skeptic ARC's into believers and allies and bring hope into their freedom and Justice of their own, about Jeff.

Boma Cite
Boma Cite is a mineral looking Boma in texture, but is truly the creation of Fake News. It was ordered by Bella to make everyone think she is the same son that Beast had long ago in hopes of gaining Bert's trust, thus forcing the rangers to surrender and face their deaths.

However, Beast was not manipulated by it and instead found the Outpost 5 tattooed on Valravn's left shoulder, the exact same location as his son did when Cedar Fair took over. Valravn said he had honestly not noticed it before, but each of his birdmen each had tattoos, so they might as well have been done while they were unconscious.

The rangers are able to bring him down, and later work together with Jezella/Garuda Zord to form Millennium Gigazord to do him in.

Arsenal

 * Brain Wave Staff-Whatever idea that is asked of him to spread is expelled from this

Daiomanji
Daiomanji is an alien that appeared in Mr. Hoover's origin story in how he became Twisted Timbers. He was being chased by Auto Cop (Lucas) and ultimately crashed in Mr. Hoover's farm, just before a bid party with a band of ARC's. He was ambushed by the Nitro Rangers, Mean Streak, Kate, Mike, and Auto Cop.

They ended up bumping into 9 braves: Double Loop, Villain, X-Flight, Dominator, Cobra, Ranging Wolf Bobs, Big Dipper, Possessed, and Serial Thriller who's spirit power destroyed the monster, but it was mysteriously able to regrow. It was finally eliminated by Nitro Megazord.

It is then found out Hoover/Twisted Timbers was just telling this story to the rangers before park opening at some point, most likely between episodes 24 and 25.

Arsenal
He has an alien looking sword as a side arm.

Bounty Hunter Boma
Bounty Hunter Boma is a Vietnam war themed monster in his modern appearance. He was originally known as Prophecy Boma as he looked more like a European and rode on horseback and would appear Seven years before their arrival, no matter what. A Trio of Braves were able to forward the warning, but he ended up in a similar position to Galotar as being locked up separately from the rest of the Boma and became Assassins.

He was going to help Bella capture Leviathan, and with her help could be powerful enough to destroy the others. When Wallace fell down the cliff from which he and Micheal were spying from, he received an injury.

He was temporarily replaced by Jezella (who was the 4th Nitro Blue, and the only one who's designated as IV of a form).

Despite Lizzie falling for the trap, the Nitro Rangers back up was able to end his him with their vicious attacks, and their mega machines.

Arsenal
Due to the use of a real gun from his sentai counterpart, he attained a more sci-fi bounty hunter-esque gun when brought over, despite keeping his gun casing sash for a more historical flare.

Dungeon Beast
Dungeon Beast is a dragon themed Boma that used to be a spirit that caused wildfires in the Boma Lore.

It was unleashed by Wyatt alongside Bella and Lizzie's assault on the rangers. It ends up being defeated by Micheal, Xavier, Mel, Fiona, and Rachel's Battalized modes.

It is later grown into a giant beast that Wyatt can control, that is destroyed by Millennium Gigazord. However, Wyatt survived to fight another Day.

Arsenal
It does what all dragons do, spew fire. It can also become a beast that can be controlled like a robot

Sealer Boma
Sealer 32-44-13 is a Boma Guardian created by the Braves to guard the Boma Mine. However, it was manipulated by Son of Beast and turned into an Emerald dragon with the code 32-44-13 being the number to break the final seal of the Boma Mine.

However, Leviathan's return to the Geauga Society has stalled these plans, so he plans to execute her any any other ARC in his way.

During the onslaught, Kate finds her "twin Power" (as she is a hybrid of Mean Streak and herself), which fractures him, but just reassembles himself as a giant and unlocks the seal, declaring the Coaster War and "The End of Time as its known".

He is destroyed by Millennium Gigazord, and explodes at the sight of the remaining ARC's for their day of judgement

Arsenal
He has a giant key staff that can create electrical charges.