I found the purple pillar, the sand castle, and the boss fight orbs, but how do i get a fourth?
There is a pit on the first floor that leads you to a puzzle room with a button above the mana shard slots. There are several solutions to this puzzle, and the cyan one leads you to the last orb.
Got it, thanks :3
How do you complete the sand castle puzzle?
You'll need an item sometime dropped after shape fights. After that, discard it from your inventory and drag & drop it onto the sandcastle.
