Update 10/21/2018: The initial version of this post had incorrect information in it: stating that Wills and Jackson were both new to the Power Rangers franchise. Their information has been changed accordingly. Thanks again to @johnpgreen for pointing out the mistake.
Some new voice actors, and some old were part of the Halloween themed episode of Power Rangers Super Ninja Steel: including a past Ranger.
James Davies as “Spoil”
Best known for his role as Chase Randall, the Black Dino Charge Ranger, James provided his voice as one of the mummy guards in this year’s episode. Originally named “Rot” and “Decay” in their first appearance in Power Rangers Dino Charge, the mummies were named “Spoil” and Putrid for Super Ninja Steel. Davies was caught in a picture with Nico Greetham, and in an airport picture with Peter and Yoshi Sudarso many assumed he’d appear in the 25th anniversary special “Dimensions in Danger.”
Scott Wills as “Putrid”
Wills, of Gail Cowan Management, has lent his voice to the Power Rangers franchise in the past before voicing the second mummy guard in this episode. Most recently, he has previously voiced “Gold Digger” and “Spell Digger” in Power Rangers Dino Charge.
Campbell Cooley as “Pumpkin Judge”
More specifically the “Right Pumpkin Judge”, Cooley adds to his list of monster voices provided for the franchise. In Power Rangers Ninja Steel, Cooley has also provided the voice of “Cosmo Royale” and “Ripcon.”
Jeremy Randerson as “Pumpkin Judge”
Randerson of Johnson&Laird voiced the “Left Pumpkin Judge” in Monster Mix-Up, reprising his role as the pumpkin judge from Power Rangers Dino Charge’s episode, “Trick or Trial.”
Andrew Laing as “Pumpkin Judge”
Laing has many credits with Power Rangers, most recently voicing “Lavagor” in the premiere episode of Power Rangers Ninja Steel, “Return of the Prism.” He played the final Pumpkin Judge, the “Middle Pumpkin Judge” in the Super Ninja Steel Halloween special.
Jeremy Birchall as “Shelldax”
Birchall also previously voiced “Megamauler” in the Super Ninja Steel episode, “Happy to Be Me.”
Jay Simon as “Versix”
Simon has also been credited as “Gorrox” in Power Rangers Super Ninja Steel but has yet to appear in an episode (he will appear in episode 19).
Emmett Skilton as “Stabberous”
While “Stabberous” was thought to be the original name for a previous character, “Dreadwolf,” that turned out to not be true. However, they were both voiced by Skilton. Skilton also previously voiced “Professor Stricker” (known as “Teacher” in the toy form) in Power Rangers Dino Super Charge.
Lauren Jackson as “Plasmora”
Jackson of Auckland Actors is not only voiced the character of “Plasmora” in “Monster Mix-Up,” whose costume was re-used from Necrolai (seen in may audience shots of Galaxy Warriors) from Power Rangers Mystic Force, but she also voiced the chameleon face of Chimera in Power Rangers Mystic Force.
Stephen Brunton as “Fangore”
Brunton lends his voice to the third Power Rangers character of the Neo-Saban Era of Power Rangers, “Fangore.” Previously, he voiced “Smellephant” in Power Rangers Super Ninja Steel premiere episode “Echoes of Evil”, and “Crustor” in Power Rangers Super Samurai.
Daisy Lawless as “Jabberon”
Daughter of Lucy Lawless, Daisy is also a newcomer to Power Rangers and voiced the character of Jabberon. Lawless is part of the Big Mouth voice agency.
Gareth Williams as “Ackshun”
Williams rounds out the vocal talent for the new monsters appearing in “Monster Mix-Up.” Of Johnson&Laird management, Williams is also a newcomer to the Power Rangers franchise.