Skelly

Skelly is one of three items in the Shadow Item Pack, a gamepass that cost 1,299 Robux and now sits on the Gamepasses page as offsale. That list names the other two items as Nightblade and Darkfire, so the pack worked as a small dark-themed bundle with a pet at its center.

The pet is easy to picture. It resembles the skeleton of a bird, but its bones are colored black instead of the usual bone white. That is the entire description the wiki offers; there are no abilities, no unbox chance and no event attached, because Skelly never came from a box or a seasonal reward.

Rated godly, it now reaches players only through trading. Anyone who wants all three pieces of the pack together will have to hunt for Nightblade and Darkfire separately, since the gamepass that sold them as a bundle can no longer be bought. The wiki does not name an official set for these three, so treat the pack list as the only confirmed link between them.

In short, the confirmed facts are the source, the price it had, the offsale status and the look.