Full 'name': Cubone-with-the-hard-head (this being more of a description. It doesn't really work in a human language.)
Possibly the youngest being in Team Rocket without counting resurrections, clones, AIs and abominations-of-nature-unto-Arceus; Cubone is a twelve-year-old pokémon, looking like most others of his species. Cute and scrawny.
His bone helmet is rarely taken off; and even when it is not in public is Cubone can possibly avoid it. You'll probably first come aware of him when you look by your feet and see the bone-wearing reptile-like pokémon and see him smiling at you, stump tail wagging and a cheerful "Hi~!" exclamation.
If you kick him at this conjecture; you could be Jesus and you're going straight to hell.
Nigh always cheerful and optimistic; Cubone acts like the child he is. There have been exceptions to this rule; his ritual to the slain guards at an attack on the base had him remove his helmet and recite a few sentences over the bodies; evidently a "Ashes to Ashes, Dust to Dust" style speech. Another exception would be his fight with Kenpachi's Xatu, where he became furious at being thought he was a push-over.
Confident in his abilities, perhaps over-confident, Cubone rarely seems fussed by fights; often confused as to the apparent lack of skill and strength involved. Although considering Cubone was able to defeat several members of the Garmy, it's possible his confidence is founded on fact. (Hint; no. He's not unskilled, but he simply isn't that good. All he has is a surprising amount of raw power. Rock-shattering with a punch level.)
On meeting anyone he doesn't immediately recognize as an enemy; Cubone inevitably introduces himself. "Hi~! I'm Cubone!". This has an advantage where even if you had stormed into the room JUST to kill something, it's doubtful you would feel anything but a desire to cuddle him.
Cubone seems to dislike bird pokémon, as they can dodge his club's strikes annoyingly well. He also dislikes grass draining abilities particularly. Complaining that they feel like acid.
Not much. Currently without a bone club, and using a metal morningstar; Cubone's combat skills have been reduced. Add to that a limited understanding of the local language and Cubone isn't the best person Team Rocket could have hired.
On the other hand, the kid's got tons of raw potential. Hammering away at his ignorance with books from the archives, large amounts of knowledge on myths and legends told amongst pokemon and survival skills to survive pretty much anwhere, Cubone is a tough little guy when it comes down to it.
Living in the mountains around Lavender Town, Cubone learnt a lot of the ceremonies (pokemon and human) for the dead. As well as his folklore from his mother. A Marowak of the area (father assumed to be dead.).
Unfortunately, this was not to last. His mother was captured by a passing trainer and, distraught he went in the same direction his mother took. Eventually stumbling on Team Rocket's headquarters, he noted many trainers went through the city. Resolving to stay there until he saw his mother, Cubone got himself involved with Team Rocket fairly quickly. Having Honchkrow as a mentor he learnt the rudiments of the language and moved into the abandoned sniper post on the floor below. (Rather... rustic. Central fire-pit with nest and 'windows' just openings to the sky. He's wild-born. He likes it.)
After Honchkrow's death, Cubone buried him in the ancient manner only carried out by Cubone and Marowak in practice. Later reclaimed a bone from the grave, which remained stong and light. Possibly with extra abilities, though as-yet unseen.
Has returned to his home-mountain. And guards it to this day, apparently a wiser Cubone. Desecrate it at your peril, stories are already in the region of a abormally stong Cubone with a swift club that seems to blaze with flame.