Prism Grunt 303

Polaris Astrophel, also known as Prism Grunt 303, is the middle sibling between Red Eyes and Blue Eyes of Oblivian notoriety. Apparently struck and killed by a train, even they are perplexed by their return to life and newfound immortality.

Personality
303 is usually the odd one out. While they can be the life of the party, it's rare for someone to want to befriend them. They're extremely reckless and carefree, loving to take risks just because they can. Their newfound status as a Laughing Dead has only increased this impulsive behavior.

Early Life
Polaris was born the middle sibling after Eta Carinae and before Antares. Each of them chose a different Johto starter, Polaris with Chikorita. The two quickly bonded and became inseparable.

Death
At some point, while playing with Antares, young Polaris was struck and killed by a train. Antares was scarred by the event, leading to him developing emotional issues.

Revival
Polaris awoke suddenly with no memory of their death. Despite dying young, they were somehow at the age they would have been had they survived. Not knowing where they were or how they got there, they sought out their siblings, and found them to be in prison due to aiding the Pinchers in Oblivia.

While still visiting their siblings often, they were drawn to Team Prism and its reputation of chaos.

In Prism
Polaris joined Team Prism and took on the role of Grunt 303. While in Prism, they used some of its resources to hijack an armored vehicle that was transferring their siblings to a different prison. They aided their siblings in escape, and hid them in an unknown place.

303 took part in defending the Kanto base from Morgan, who had come to retrieve her child, Grunt 94. In the process, 303 was unknowingly bitten by 94.

303 befriended Grunt 3 due to an inner chaos the two shared. Together, they decided to investigate the Ironwyrm Spire, a ruined tower in the Galar Wild Area that was supposedly the hollow corpse of a Gigantamax Duraludon. While attempting to play the elevator game, the two were briefly separated, and during this time, Tantou of the Scarlet Court approached 3 and revealed that 303 was a Laughing Dead.

After 3 used their own special sight to verify Tantou's concerns, Team Prism formed a hesitant alliance with the Scarlet Court in the hopes of curing 303's disease. After months without a cure, the Court eventually took 303 away to place them in a special containment. It would stop their soul from rotting further, but would render them unconscious until their eventual release. Though 303 attempted to resist, they were taken away, and have not been heard from since.

Familial
Little is known about 303's family, with the exception of their two siblings. Supposedly, the three were adopted.

Romantic
303 has never had a romantic partner. They have a crush, and have dropped hints to their crush a few times, but are unsure if they should ever really act on it. They doubt their crush has any feelings for them, anyway.

Prism Grunt 3
Prism Grunt 3 seems to be 303's closest friend in Prism, and the two have bonded over shared love of risks and the paranormal.

Lotus (Male Shiny Meganium)
Lotus is 303's partner Pokémon. Being an White City variant shiny, he looks quite different from others of his kind. In the years between 303's death and return, he was raised and evolved by Blue Eyes, and battled at her side.

Sappy (Female Pansage)
Quiet and cheery, Sappy loves to get her paws into whatever mischief she can. She and Hopskotch are frequently heard running through the air ducts of Prism bases.

Hopskotch (Male Grookey)
Hopskotch and Sappy go together like peas in a pod, quite literally - they become anxious and cannot sleep unless they're in the same dog bed. Hopskotch is one of 303's more recent catches. They have failed to provide an explanation for why his name is spelled incorrectly.

Poppy (Male Amaura)
One of 303's two non-Grass-Type Pokémon, Poppy is fairly shy, but very vocal. He can often be heard chirping from 303's room, but if anyone comes to check on him, he immediately goes quiet. No one's sure what he wants when he does this, since he seems content.

Roomba (Female Shiny Kabuto)
Another Orre-variant shiny, Roomba was named for her metallic coloration. She can often be seen wandering the halls, delivering small items on her back.

Trivia

 * 303 is one of few characters in the Prism universe to be related to canon Pokémon characters. In 303's case, these characters are Blue Eyes and Red Eyes from Pokémon Ranger: Guardian Signs, who are their siblings.
 * Ironically, 303 is colorblind, having deuteranopia. Even more ironic, deuteranopia is classified as "green-weakness".
 * This was discovered when 303 could not tell the difference between types of apples.