A Monster's Expedition

Auto-unlocks once you make your first real move off the starting island.

Fast-travel via a red mailbox - once you've found at least two post boxes, use one to warp to another.

Step onto a sit / relax spot at the water's edge so the monster sits down. (A description-confirmed relax interactable; the exact island is not pinned here.)

Progression - later you loop back and re-approach earlier islands from a new direction.

Progress far enough along the chain to reach the windmill landmark (a pun on "for sale").

A late-game story beat - a scripted "friend" moment on the route to the finish, just before the ending.

The ending - complete the expedition and board the final ferry home.

Walk up to and read every museum exhibit sign in the game. There's no in-game checklist, so use an exhibit-locations guide or the community map. Exact exhibit count not confirmed here.

The rarest one - find and hug every hidden snowman scattered across the islands. No in-game checklist, so use a snowman-locations guide or map. Exact snowman count not confirmed here.