Ammit

Summon by using the Pyramid Crystal in the middle of Dark Star Lord's Mausoleum B1-C1.

He will either breathe fireballs high or low a few times, and then jump.

When he breathes fireballs high, you can duck under the lowest one.

When he breathes fireballs low, you can double-jump between them or use a shield.

When he jumps, run underneath him.

The fight is made particularly tricky by the fact that normal enemies keep respawning during the fight.

Reward: A chest that appears alongside him opens, containing the Vessel, and the alligator statue in B-7 moves into place, allowing you to read the tablet in that room.