Mental Fatigue

Level             Effect                                                                                                                   

1                         Disadvantage on all Intelligence, Wisdom, and Charisma checks. 

2                         Disadvantage on Concentration checks.

3                         Disadvantage on Intelligence, Wisdom, and Charisma saving throws.

4                         You can’t concentrate on spells; all concentration spells have a duration 

                 of instantaneous.

5                         You are Stunned for 1d4 rounds.

6                        You fall Unconscious.

 

You can be brought back to consciousness by a healing spell or potion, lesser or greater restoration, or a medicine check DC 15.

Even after regaining consciousness you are still treated as having 6 levels of mental fatigue, therefore any thing that causes mental fatigue means you fall unconscious again.

An effect that reduces exhaustion reduces mental fatigue as well.

Finishing a long rest reduces a creature’s mental fatigue level by 1, additionally for every 8 hours a creature spends doing no more than light activity it reduces it’s mental fatigue level by 1.