Master Xandred

Master Xandred is the leader of the Nighloks. He is the primary adversary of the Samurai Rangers. He comes from the Netherworld and lives on a ship floating on the Sanzu River. It is revealed that he takes large doses of medicine for his frequent headaches (similar to Rita Repulsa's), often causing him to fall asleep. He becomes angry easily, especially if his henchman are insubordinate or speak out of turn. He also has an intense hatred for Deker, since Deker intervened in one of Master Xandred's plans(which also involved Jayden, the current Red Samurai Ranger).

For generations, the Samurai Rangers had battled Master Xandred and the Nighloks. At some point during the war, Jayden's father (leader of the 17th generation of the Shiba Clan) seperated Jayden and his sister Lauren just so Lauren can master the Sealing Symbol while Jayden fills in as the 18th Generation's leader until she returns. During one battle against the Nighloks, Xandred defeated the 17th generation of the Shiba Clan. Before he had time to celebrate Jayden's father managed to seal Xandred away.

Years later, Master Xandred returns after being sealed temporarily with the help of Octoroo sending Nighlok monsters to cause misery. Xandred states that it was a good thing that he defeated the Power Rangers but Octoroo reminds him that he was sealed by Jayden's father and the rangers are back causing him to get angry. He resumes command of the Nighloks to cause more human misery.

In "The Tengen Gate" when Arachnitor tries to usurp him, Xandred transforms him into a mindless mutant, due to Xandred having gained increased powers.

In "Boxed In" Xandred orders Dayu to destroy Deker, only to get her harmonium burned in "Broken Dreams". After Burning Dayu's harmonium, Xandred's rage became unbearable, which was made worse when he formed an alliance with Serrator in "Something Fishy".

In "The Master Returns", Xandred learns of Serrator's treachery so he returns to the human world to gain back Dayu's Harmonium, only to dry out severely, due to being so far away from the Sanzu River. Octoroo was able to save him and bring him back to the ship. Master Xandred is currently recharging at the bottom of the Sanzu River. Before that, Xandred managed to fix Dayu's harmonium and severely wound Jayden.

After a lengthy period of recuperation, Xandred eventually returned and faced the Samurai Rangers now led by the true Red Ranger, Lauren. Running into a wounded Dayu, he schemed after she reminded him she was half-human and absorbed her. He then faced the Samurai Rangers, while Lauren drew the sealing symbol. Despite his best effort to stop her, the symbol was completed and used. However, while it caused massive damage, it didn't manage to seal him as expected, since Dayu's humanity had protected him from the symbol's power. Also, Xandred was no longer in danger of drying out and planned his takeover of the human world. He then defeated the Rangers and wounded Lauren.

When the Sanzu flood waters overflowed, Xandred released him army of Moogers to lay waste to Panorama City. The Samurai Rangers, now led by Jayden again, took on and defeated the Moogers before facing Xandred. After significantly weakening him with Shiba fire power, Jayden defeated him with the Shogun armor.

However, Xandred transformed into his Mega Monster form and the Rangers called on the Gigazord to fight him. As the Rangers attempted to get close enough to use a final blow filled with symbol power, Xandred blasted away the zords one by one until only the Samurai Megazord remained, which managed to succeed and strike Xandred with a fatal blow. However, Xandred unsuccessfully tried to take the Rangers with him by grabbing the Megazord and boasting, before he was destroyed, that the Nighloks would rise again someday. He was then consumed in a massive explosion, finally being destroyed for good. After he was destroyed, the Sanzu River flood waters receded back into the Underworld.