A mysterious dreamer
A character that makes his first appearance in Act 34 as the mythological hybrid between a Pegasus and Unicorn, the priest of Elysion, Helios is one of the more mysterious protagonists of the series.
"You have the power to save me...to save everything. A Princess, yet a soldier protected by the moonlight...A maiden with a beautiful dream. The chosen maiden who holds the crystal that shall melt the seal of the Golden Crystal."
Helios, Act 39
Helios appears before Chibiusa and Usagi during a solar eclipse asking for the "maiden" to help him. However, it is unclear who Helios was asking as both Chibiusa and Usagi believe they are the "maiden." Mamori also witnesses this strange vision, while others around them only see the eclipse. Helios appears again, this time only to Chibiusa in her dreams and promises to give Chibiusa strength in return that she rescue Elysion by finding the Golden Crystal. Helios then gives Chibiusa a bell, which will allow her to call on Helios when needed by speaking "Twinkle Yell!"
As the arc progresses, Helios reveals that the Golden Crystal he is searching for is found in Mamori. Helios is one of the few characters that addresses Mamori as Prince Endymion throughout the series as it is originally the Prince of Earth that holds the Golden Crystal, similar to the Silver Crystal of the Moon Princess. Helios later recalls that he first had a vision of "Princess Lady Serenity" in her adult form as the one that can unlock the Golden crystal. Unfortunately the maiden that is foretold to unlock the Golden Crystal is Usagi, not Chibiusa. In Act, he finally reveals his human form to kiss Chibiusa, when she finds out that Usagi is the maiden called in the prophecy.
"Little maiden rescued me...my maiden has always been right in front of me."
Helios, Act 42
After the battle with Queen Nehelenia, Helios is supposedly dead after using up all of his power. Chibiusa is able to revive him as well as produce her own power in the form of the Pink Moon Crystal with a kiss. After he is revived he notes to himself how the maiden he has always been looking for was right in front of him. Helios returns the Golden Crystal to Prince Endymion and this triggers a powerful reaction that transforms everyone temporarily into their future forms of King Endymion and Neo Queen Serenity. As it is their fate to return to their own worlds, Helios promises that they will meet again someday and Chibiusa she will await his return when she becomes a true lady.
Takeuchi Naoko notes in her Materials Collection that, "his image has the feeling of the young Prince Endymion (in his previous life). For his color as well, I want to use what was used for Endymion."
She also indicates for one of her images in Artbook 4 that Helios "is wearing some awfully strange clothes eh? If I remember correctly, I didn't have much time, so when I drew him I threw on some easy to draw clothes, deciding that those would be adequate. Now I think the ugly design of those clothes really is a disaster."
Click the images on the left for translated Material Collection notes.
Chibiusa is unsure whether Helios is an unicorn or a Pegasus horse when he appears before her again as he seems to have a horn on his head like a unicorn, but has the wings of a Pegasus. When Helios finally introduces himself to Chibiusa he calls himself the Pegasus, Helios. At the closing of the Dream arc, Helios calls Pegasus his favorite and most noble steed. To rectify the confusion, Helios is human, but his body was captured by Nehelenia and fused with Pegasus. According to Takeuchi Naoko's Material Collection notes "There are times when you can catch a glimpse of him in human form instead of Pegasus form. A gold horn sticks out as a sign of the magic cast on his captured body." At the end of the Dream arc, Helios is freed from his fusion with Pegasus and is seen in his human form without the horn.
In Greek mythology, Pegasus is a winged horse. He is sired by Poseidon (god of horses) and Medusa. When the Greek hero, Perseus, cuts off Medusa's head, Pegasus was thought to have sprung forth from her body. There is one story, two versions that involve Pegasus.
When he was drinking from a lake, the hero Bellerophon was able to capture Pegasus using a golden bridle given to him by Athena. The gods then allowed Bellerophon to keep Pegasus to kill the Chimera. However, when Bellerophon tried to mount Pegasus, he threw him off and flew to the heavens where he became a constellation. The other version of story indicates that Bellerophon tried to use Pegasus to fly to Mount Olympus, city of the gods. Zeus became angry and sent a gadfly to sting Pegasus, who threw his rider to his death. It is said that Pegasus reach Mount Olympus and that he still resides there.