A monster party of Egyptian myth.
The undead is, of course, the mummy. Someone broke into his afterlife-house and stole all his shiny things, now he is not happy.
The lizard is not really a lizard, but the Chaos Serpent Apep, who every night tries to devour the Sun on its journey under the Earth.
The beast is Ammit, who is crocodile, lion and hippo, the three most feared animals of Egypt. She sits at the entrance to the Underworld and is the goddess of eating sinners' hearts, should they be found so burdened with guilt as to be heavier than a feather.
Finally, the demon is not a real mythical character, but a humanoid resembling Set, the god of foreigners and the red desert. Though he was often depicted as villainous, especially during the periods when Egypt was ruled by the foreign Hyksos, Set also has a role in the journey of the Sun, where he kills Apep with a spear every time.