One of the puzzles should be a circle... just for the hell of it.
It'll surprise the player to see a circular puzzle piece.

All puzzles still need to be assembed on a grid, but their outer edges can theoretically be ANY shape.

And if I wanted to go overboard with the overlap, I could have one outer edge one puzzle-piece just stick-out surprisingly far.

Or I could have a picture with multiple characters in it and cut-out the pieces to match parts of their silhouettes.

Or create pieces in the silhouettes of characters and they just need to be matched up with another corresponding character. The finished image reveals who the character is. The top halves could hold hands. The bottom halves could be a guess about what shoes they wear.
... or
the bottom halves are their entire bodies, holding hands, and the top halves are just their heads.
	(match character with character, and match outfit with its character)
	(witch + ridinghood?  Their different heights might mess with it)
... or
character on bottom + animal/person on top
	(match a character with their preference)

Multiple finished puzzles can be placed next to each other to reveal something.
	Maybe they're parts of a map or a treasure map?




These unexpectedly weird pieces should not start appearing until mid to late game.