Nighloks
The Nighloks are monsters used by the villains to attack the Human World. They are adapted from Samurai Sentai Shinkenger. They are dependent on waters from the Sanzu River for survival, therefore needing the negative emotions of humans to keep it from drying out. They are trying to expand the Sanzu River to make it flood into the human world so the Nighlok can rule both worlds. When a Nighlok is destroyed once, it can grow into a giant Mega-Monster on its own that the Rangers need to use the Megazord to defeat. When a Nighlok is destroyed, it ends up in the Nighlok Heaven. All Nighloks have a ability to enter the living world through cracks and narrow gaps.
Tooya
Tooya is a Nighlok with a second face on his skirt and was the first Nighlok that the Samurai Rangers had fought. He can breathe fire. He led the Moogers in attacking the city until the Samurai Rangers arrived. After the Moogers were defeated, Jayden engaged Tooya in battle and manages to defeat him. Tooya then grows to giant size and the Rangers unleashed their Zords as they attack Tooya. The Lion Folding Zord destroys Tooya. Tooya appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
Origins Part 1 and Party Monsters
Scorpionic
Scorpionic is a weasel-like Nighlok with scorpion-like armor. He is armed with a scythe and uses his mane to create gust of wind to hit his opponents. He was sent to terrorize humans by causing massive damage and gathering all humans in the area. Scorpionic is the first Nighlok to be slain by the Samurai Megazord. Scorpionic appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks
Origins Part 2 and Party Monsters
Rofer
Rofer is an arrogant Nighlok. He can extend his arms to attack from long distances under the ground. Mike manages to outwit Rofer and defeat him with Samurai Megazord finishing the enlarged monster off. Rofer appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
The Team Unites and Party Monsters
Doubletone
Doubletone is a two-toned Nighlok that is armed with the a Bamboo-like spear. The right side of his body is tiger-like while the left side is Kappa-like. Summoned by Octoroo, Doubletone is sent to increase the River by doing what he loves best, shattering people's dreams. Appearing in the mortal realm before a boy named Ryan, Doubletone accomplish his goal by tricking the boy with a false promise of seeing his father again if he gives up baseball. He is defeated by Kevin and Mia and then destroyed by Samurai Megazord. In "Party Monsters, Doubletone appears at a Halloween Party at a club in the Nighlok Afterlife.
Deal with a Nighlok and Party Monsters
Dreadhead
Dreadhead is a dreadlocked, western-accented Nighlok. He wields a shotgun and immune to any physical attack. He meets his end when the Rangers utilize the Beetle Disk to create the Beetle Blaster Megazord. In "Party Monsters," Dreadhead appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
Day Off and Party Monsters
Negatron
Negatron is a Nighlok who uses insults as a weapon. He has three eyes: one on the bottom left, one on the bottom right, and one above them in the center. Emily was the only one unaffected by his insults. He is defeated by Jayden's Cannon Blast and then destroyed by the Beetle Blaster Megazord. Negatron appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks. During the party, he had a Mooger take away the Candy Worms and replace them with real worms.
Sticks & Stones and Party Monsters
Yamiror
Yamiror is a tree-like Nighlok with a breath that can poison or paralyze others. His poisoning gas can be cured by the purifying water of the Swordfish Disc. He is defeated by the 5-Disc Swordfish Cannon and then destroyed by the Swordfish Fencer Megazord. Yamiror appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
A Fish Out of Water and Party Monsters
Madimot
Madimot is a Nighlok that wields a large shield with spikes on them. He is also able to shoot dark energy from his face which he uses to control others minds. He has the control of the Tiger Zord. Kevin is hit by his dark energy attack. Jayden used his symbol power to break his hold on both Kevin and the Tiger Zord. The Tiger Zord then helped to destroy Madimot. Madimont appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
I've Got A Spell On Blue and Party Monsters
Desperaino
Desperaino is a Nighlok who summons rain that causes loss of hope and unfolds his head like an umbrella to fly. Desperaino is defeated by the Green Ranger's Spin Swords - Tree Symbol Strike and then destroyed by the Samurai Battlewing's Final Strike finisher. n "Party Monsters," Desperaino appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
Forest for the Trees and Party Monsters
Robtish
Robtish is a Scottish-accented Nighlok with 2 squinted eyes and red skin, wears a helmet with spikes, and has a fierce grin with fangs. He wields a sword in battle and can unleash a sonic shockwave that is followed up by a Double Slash technique. Robtish is sent to take out Jayden and first appeared in the form of a swordsman. The other four Rangers had to defend Jayden and ended up injured in the process. Robtish ends up retreating after being wounded by Deker who claims that Jayden is his target. Robtish is sent back to the city to attack Jayden again. Robtish ends up leading the Moogers in attacking the park in Harper Village. Jayden ends up fighting Robtish and Moogers until the others arrive. The Rangers transform, defeats the Moogers, and ends up fighting Robtish. After the Rangers blocked Robtish's attacks, Robtish is defeated by the Five-Disk Tiger Cannon. Robtish grows to giant size and the Rangers summon the Samurai Megazord. The Samurai Battlewing Megazord then destroys Robtishr. Robtish appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battles with the Rangers to the other Nighloks.
Test of the Leader, Jayden's Challenge and Party Monsters
Vulpes
Vulpes is a fox/crow Nighlok who spied on Jayden to find out of his Symbol power to seal Master Xandred with his mirror called the "Enchanted Eye". He has a ton of Mirror spells. He can open a portal to reflect back the Rangers sword attacks, can copy their sword slash attack, summon energy crows, and use his Fox Veil to become invisible. When it comes to his recent spying on Jayden on the sea shore, he ended up heading up to Spring Valley when he lost visual of Jayden. Vulpes arrived on at Spring Valley where Jayden ambushed him and stole Vulpes' mirror. Jayden revealed that Vulpes' mirror can't work if the person is in pure water. After destroying Vulpes' mirror, Jayden, Kevin, and Mia called for Mike and Emily to help fight Vulpes.

When the Rangers activated the Spin Swords, he used his Fox Reflector to take down the Rangers. Just then, the mysterious fish vendor the Rangers were chasing earlier arrives and turns into the Gold Ranger and ends up fighting Vulpes alongside the Moogers. After the Moogers were taken down, Vulpes is taken down by the Gold Ranger's Barracuda Blade. Vulpes then grew to giant size and the Rangers form the Samurai Battlewing Megazord. Vulpes then made himself invisible and attacked the Rangers.

The Gold Ranger summons the Octozord which uses its ink cloud to reveal Vulpes and attack him. Vulpes is then destroyed by the Samurai Battlewing Megazord's Mega Blade. In "Room for One More", it was revealed that Vulpes was good friends with Steeleto. Vulpes appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
Unexpected Arrival and Party Monsters

Steeleto
Steeleto is a Nighlok who can attack with his Full-Body Blades attack and can perform the Steel Blade Scatter Shot attack. He goes to fight the Power Rangers to avenge his friend Vulpes. He ends up attacking an underpass where the Rangers end up fighting him. Steeleto nearly defeating the five before he falls back into the Sanzu River when he starts to dry up. By the time he resumes his campaign of vengeance at the Northern Peninsula Construction Site, the Power Rangers have the Gold Ranger by their side and attacks them with the Moogers.

Steeleto is defeated by the Red and Gold Rangers' Barracuda Bite and Blazing Strike finishers. Steeleto then grows and the Rangers form the Samurai Megazord. Steeleto was overwhelming the Samurai Megazord with the Full-Body Blades attack until Antonio summoned the Octozord. Antonio then combined the Octozord with the Samurai Megazord to form the Octo Spear Megazord which destroys Steeleto with its Samurai Strike attack. Steeleto appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
Room for One More and Party Monsters

Antberry
A slimy Nighlok whose body is full of slime. He spits the slime on the Rangers so they can't pick up their weapons. Antberry is defeated by a combination of Blue Ranger's Dragon Splash and Gold Ranger's Barracuda Bite. Antberry then grew to giant size. Antberry is destroyed by the Octo Spear Megazord's Electric Spear finisher. In "Party Monsters," Antberry appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
The Blue & The Gold and Party Monsters
Splitface
Splitface is a multi-faced Nighlok who steals people's spirits. He does this to make his victim's loved ones sad so the Sanzu River would rise. He stole Emily's spirit and a group of civilians' spirits. After stealing Emily's spirit, he told the Rangers he was going to the Netherworld and staying there. With enough symbol power, the Rangers drew Splitface out of the Netherworld. All of the spirit's he stole were returned when he was defeated by the Claw Battlezord East. In "Party Monsters," Splitface appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battles with the Rangers to the other Nighloks.
Team Spirit and Party Monsters
Arachnitor
Arachnitor is a Ushi-oni-like Nighlok who wants to get rid of Master Xandred in his desire for power. His plan includes using the same sealing symbol that is used on Master Xandred in the past generation, but he needs Octoroo's help to get it. When Octoroo poisons the team's drinks while they are at Tengen Temple, Jayden takes a sip and becomes sick. While Arachnitor takes on the Samurai Rangers, Octoroo demands the sealing symbol in exchange for the antidote that would cure Jayden. Antonio, who has been distracted by cooking for the man he does not know is Deker, arrives to find everyone gravely injured, and he helps them take Jayden to a safe place. As punishment for defying Master Xandred, Arachnitor is dragged back to the Netherworld and is mutating thanks to Master Xandred's newfound power.

In "Boxed In", Master Xandred's power turns Arachnitor into a mindless Nighlok and Octoroo is ordered to send Arachnitor back to Earth once he is finished mutating. When that is done, Arachnitor is sent to Earth and attacked the city. While Antonio works on the Black Box by adding the powers of each Power Disk to it, the other four Rangers fight Arachnitor. Although Arachnitor overpowers the Rangers, Jayden and Antonio arrive in time to gives the Rangers their Power Disks back. The Rangers are able to knock Arachnitor down with the Quintuple Slash. Combined with the Rangers' Quintuple Slash, Antonio uses a spin attack to knock down Arachnitor as giant Moogers attack the city causing the Rangers to form the Megazords. While the Rangers fight the Giant Moogers, Arachnitor escapes. Once the Giant Moogers are destroyed, it was stated by the Rangers that Arachnitor is half-way back to the Netherworld by now.

In "Super Samurai," Arachnitor resurfaces and is causing despair near a forest. Mike uses his knowledge of the forest to find Arachnitor with the other Rangers. Emily points out he's the one that "got away". He is able to knock down the Rangers before he flies away to a seemingly-abandoned work site where there are puddles of water from the Sanzu River. Using the power of the Black Box, Arachnitor was defeated by Red Ranger/Super Samurai Mode. Arachnitor then grows as Octoroo summons some Giant Moogers and two Spitfangs to help Arachnitor. The Rangers form the Samurai Megazord to fight Arachnitor, the Moogers, and the Spitfangs. Arachnitor is finally destroyed by the Claw Armor Megazord and the Samurai Battle Cannon (which was used against Arachnitor and his pair of Spitfangs).
The Tengen Gate

Rhinosnorus
Rhinosnorus is a rhinoceros-like Nighlok with a sideways elephant-like head behind his head. He is sent by Master Xandred to put Dayu to sleep and allow her to remember her origin by exuding a sleep-inducing mist from an inducer on his left arm. Once his job is done, he then enters the Dream World so he can eat the dream incarnations of his human victims. However, Mike and Kevin enter the Dream World after him and force the Nighlok out and break his mist inducer. Rhinosnorus escapes to Netherworld. Rhinosnorus returns the next day with the Moogers, he is defeated by Kevin with his Hydro Bow and destroyed by Samurai Megazord. Rhinosnorus appears at a Halloween Party at a club in the Nighlok Afterlife and recaps his battle with the Rangers to the other Nighloks.
Broken Dreams and Party Monsters