What is Exhaustion?
Some special abilities and environmental hazards, such as starvation and the long-­term effects of freezing or scorching temperatures, can lead to a special condition called exhaustion. Exhaustion is measured in Eleven levels. An effect can give a creature one or more levels of exhaustion, as specified in the effect's description.

Gaining Exhaustion:
Falling in Combat, Using a Spell of a Slot Level that is Exhausted, Creature Effects, Starvation, Extreme Weather and Conditions, Lack of Rest, among other means.

Ending the Condition:
Finishing a Long Rest removes 1 of your levels of exhaustion. When your exhaustion level reaches 0, you are no longer Exhausted.

Levels of Exhaustion:
This Condition is cumulative. Each time you receive it, you gain 1 level of exhaustion. You die if your exhaustion level exceeds 10.

D20 Rolls Affected:
When you make a d20 Test, you subtract your exhaustion level from the d20 roll.

Spell Save DC's Affected:
Subtract your exhaustion level from the Spell save DC of any Spell you cast.

Special Ability Save DC's Affected:
Subtract your exhaustion level from the DC of your abilities: (ie: Breath Weapon, Stunning Strike, etc).

Movement Speed Affected:
Decrease your Movement Speed by 5 for each level of Exhaustion.

 

Hitpoint Reduction:
After a creature Reaches 5 levels of Exhaustion, their Hit Point Maximum is halved.

Death:

When a Creature Exceeds 10 levels of Exhaustion, it dies.