Pumpkin Jack. It’s a 3D platformer. I haven’t played it in a couple years, but I remember it being mostly linear. Not a ton of collectables, but some. 11 months out of the year it’s a pretty “meh” game, but it absolutely NAILS the Halloween aesthetic. Not “horror” or “scary” or “autumn” but very specifically Halloween.

MediEvil is similar, though much older. I have only played the original for PS1, though there is a modern remake on all platforms that looks pretty good. Not quite as explicitly Halloween-y, but still pretty close. Flawed in its own ways, but I would still say a better game overall than Pumpkin Jack. The levels were a bit less linear and it was a bit more like an adventure game than a platformer.

Luigi’s Mansion is a classic too.

A lot of other games have levels or worlds that are good for Halloween even if the whole game isn’t. Like Pumpkin Hill in Sonic Adventure 2, or Subcon Forest from A Hat In Time. Honestly one day I want to compile a list of all of these themes areas across my favorite games and the play all of these levels seasonally.