Level 20

in level 19 we see something new.

We can see the Fighter, Thief and the Wizard all at the entrance of the room, standing there. Thou the Thief does stand out, with a golden diamond under the Thief.

Trying to move we find that the Thief moves. Switching characters, we find it moves the camera to the character we choose to switch to, now allowing us to move that character.

There're also a Lever in the middle of the entrance, pulling it, one of the Moving Platforms move, if you put someone on there, and take them to the next lever, we find the platform we're on lights up, thus the puzzle of the room, getting all 3 characters onto a platform.

Doing so we find, the platforms open up, underneath each character, making them plummet, end the room, taking us to Level 21.