|This article is about a/an ranger in Power Rangers Lost Galaxy.|
|First Appearance:||Quasar Quest (1)|
|Last Appearance:||Trakeena's Revenge (2)|
|Number of Episode|
Full list of appearances
Kai Chen is Galaxy Blue of the Galaxy Rangers.
Straight-laced, sensible, and ambitious, Kai is the classic overachiever. Having been brought up in a strict military family, he always does things by the book and likes everything in its place. His orderly world is turned upside down when he becomes a Power Ranger, and he must learn that sometimes rules are meant to be broken when it comes to saving the universe. He is apparently a good friend of Kendrix Morgan. His fighting style consists of grappling moves and throws, presumably taught by the military.
Kai was responsible for the majority of the meals the Rangers ate aboard Terra Venture. When a lovesick Kai rendered himself bed-ridden for several days after a romantic letdown, the other Rangers complained about the lack of decent food to eat, as Kai was the Galaxy Ranger who either had the greatest cooking expertise, or the only one who was willing to cook for the group.
In Lightspeed Rescue, Kai returned to Earth with the Galaxy Rangers and helped the Lightspeed Rangers defeat Trakeena for the final time. He fought alongside Chad Lee, the Blue Lightspeed Ranger and his Blue Ranger successor.
Kai and the other Galaxy Rangers returned as part of the army of Legendary Rangers that helped the Mega Rangers defeat the Armada once and for all, fighting in a huge battle against hundreds of X Borgs and dozens of Bruisers.
The Galaxy Blue Ranger Key is Kai's personal ranger key. This key along with the majority of the Core Ranger Keys are seen lining the Command Center's interior walls. This key is mainly used by Noah Carver (Super Megaforce Blue) who uses it to fight as the Galaxy Blue Ranger.
- When the Super Mega Rangers became the Lost Galaxy Rangers while fighting Matacore.
- When the Super Mega Rangers became the Lost Galaxy Rangers while fighting Gorgax.
The Galaxy Blue Ranger key is one of the five water-element Blue Ranger Keys that are used by Super Megaforce Blue for his Ultimate Ranger Saber Strike attack, which was used once against Skatana. This attack involved summoning manifestations of the five Rangers to attack the target, with Galaxy Blue being the last to go.
- Kai is the only Power Rangers character to share a first name with a Sentai character. Specifically, Kai Samezu of Gaoranger and Kai Ozu of Magiranger.
- Fittingly, one of them was also the Blue Ranger of his respective group as well, along being water based.
- In the Japanese dub of Power Rangers Lost Galaxy, Kai is voiced by Kazuki Maehara who played Leo's counterpart Ryouma in Gingaman.