Darakhul Fever

Spread mainly through bite wounds, this disease makes itself
known within 24 hours by swiftly debilitating the infected.
An infected creature must make a DC 17 Constitution saving
throw after every long rest. On a failed save, the victim takes
14 (4d6) necrotic damage, and its hp maximum is reduced
by an amount equal to the damage taken. This reduction
lasts until the victim finishes a long rest after the disease is
cured. The victim recovers from the disease by making two
consecutive successful saving throws. Greater restoration
cures the disease, while lesser restoration gives the victim
advantage on the next saving throw.
Primarily spread among humanoids, the disease can affect
ogres, and therefore other giants may be susceptible. If a
creature dies while infected with darakhul fever, roll a d20,
add the character’s Constitution modifier, and find the result
on the Adjustment Table to determine what undead form the
victim’s body rises in. ADJUSTMENT TABLE
Roll Result
1–9 None; victim is simply dead
10–16 Ghoul
17–20 Ghast
21+ Darakhul