On rare occasions, a beholder's sleeping mind drifts to places beyond its normal madness, imagining a reality in which it exists beyond death. When such dreams take hold, a beholder can transform, its flesh sloughing away to leave a death tyrant behind. This monster possesses the cunning and much of the magic it had in life, but it is fueled by the power of undeath. A death tyrant appears as a massive, naked skull, with a pinpoint of red light gleaming in its hollow eye socket. With its eyestalks rotted away, ten spectral eyes hover above the creature and glare in all directions.
Deathly Despot. As they did when they were beholders, death tyrants lord their power over other creatures. Moreover, a beholder's ability to quash magical energy with its central eye gives way to a more sinister power in a death tyrant, which can transform former slaves and enemies into undead servants.
Zombies created by a death tyrant are used and discarded as needed. They stand guard at the entrances to the death tyrant's lair or guard its treasure vaults.
Acting as bait for traps or as combat fodder, zombies keep powerful enemies distracted while the death tyrant moves into position and prepares to destroy them.
Armies of the Dead. A death tyrant that embraces undeath becomes an engine of destruction. Driven by a hunger for power and security, it advances against humanoid settlements, using its eye rays to destroy every creature it encounters, then building an army of undead. If left unchecked, a death tyrant might wipe out the population of a city in weeks, then set its undead eye on wider conquest. As each settlement falls, the death tyrant's zombie forces build to overwhelming numbers.
A Death Tyrant's Lair. A death tyrant's lair is usually the same site it held as a beholder, but it contains more trappings of death and decay. A death tyrant encountered in its lair has a challenge rating of 15 (13,000 XP).
The death tyrant can't repeat an effect until all three have been used, and it can't use the same effect on consecutive rounds.