Bao's analysis indicates that to open the gate at the bottom of the courtyard, you must first locate three "keys" to activate the three mechanisms in front of it.

I'm sure the treasure's behind this gate! But how do we get it open...

Gotta be linked to these three mechanisms by the gate... Let me see what hints this treasure map's hiding...

Looks like we'll need three keys to activate these mechanisms.

Let's go find them, Endmin!

These three "keys" are scattered across the underground first, second, and third levels.

Aha! There it is!