Sarcophagi

 are Interactive Objects in Temple Glider. There are 2 in the game.

The Gold  (left in picture) is what the Egyptian Bird starts at and needs to reach in each level of the game. The Black  (right in picture) is what the Bird is reborn through if it dies.

The Bird has to touch a Black to make it their new spawn point. If they start a level, and don't touch a Black, they will start back at the Gold when they die. When the Black is touched, the purple jewel will flash and the eyes of the Sarcophagi will turn purple.

When the Bird Dies, a purple sphere (which is probably its soul) will go back on to the jewel on the Black Sarcophagi, it will light up, and the Sarcophagi will open, revealing a Bird wrapped up, which will open its eyes, then open up its wings, ripping the wraps on it.