Death pyramid

This is small one shot in DnD. You are playing as an adventurers, that were poisoned in a tavern. Than u were send to a magic pyramid wich you can not escape. Your group have to go through a pyramid and defeate the greate undead mummy lord - Bamenheop and his minions. Pyramid has 4 lvls. Finale fight with Bamenheop takes place in pocket dimension arena.
One shot for charecters lvl 7. Mummy lord was nerfed to fit the campaign.