Marvin Shih is a great leader and a great ranger he seems familiar somehow like maybe in another life he was ranger before and magician.
Jack Thomas was a beat cop who was asked by Senior Commander Varge to do a lecture at Time Force Academy. There something would change his world he looks very familiar maybe he has an ancestor from the 1990's that hung out a juice bar.
Trent Fernadez the White Dino Thunder Ranger he is very much like Tommy in the beginning and is pretty cool I love his suit its awesome, I can't wait to see if he makes into battle for the grid game. His dream is to be artist but dad doesn't understand till later
Ancient Ogre is the main villain of 3 and comes back in 5 not much is known about him. He has done alot for the story over the years or at least the after math.
The original King yes other people have taken up the mask, talk about an iconic mask he even makes nosies to match he was an orphan and he became a priest and runs an orphanage he fights to keeps those kids safe a provide them a better life than he had. He fought ogre he died
The Green Baby is part of Pucci's master plan its made Dio's bones and multiple souls so its kinda JoJo's take on Cell from dragon ball I already reveal too much and the series is still coming out so the rest is a secret.
Donatello Versus another son of Dio's he is capable of making person relive past events of an area that they are in or close by he is the closest to Dio personality wanting to make his happiness above everyone else.
Rikiel despite being Dio's child he is surprisingly very honorable but will do more risk against tougher opponents.
Ungalo is a child of Dio yes Dio had more kids they were brought together by Pucci for his plans though he left Giorno out because probably the danger he would pose on them.
Sports Maxx is a very dangerous foe he killed Eremes' sister and his stand ability can reanimate and control the dead anything from human to animal, later even himself turning himself into a zombie.