You gain weight unrelated to diet and exercise. After every adventure or major campaign arc, you must succeed on a DC 8 + (IE) Constitution saving throw. On failure, your weight has increased by IE × 2d6 percent. On success, your weight has decreased by IE × 1d4 percent. For every fifty percent increase, you have a −1 penalty on Dexterity (Acrobatics) and Strength (Athletics) checks. For every ten percent decrease, you experience Temperature Sensitivity for 3d20 days as your body acclimates itself and must succeed on a DC 8 + (IE) Constitution saving throw or experience Fatigue until you succeed on the saving throw, which you can attempt daily after a long rest. You have a +(IE) bonus to Strength (Athletics) checks for swimming.

Real-world Examples

Hypothyroidism, Depression, Insomnia, Menopause, Cushing’s Disease, Polycystic Ovarian Syndrome, Congestive Heart Failure, Sleep Apnea, Edema, Diabetes, Down Syndrome

Assistive Options

Because this gain is unrelated to diet and exercise, little can be done besides acceptance.

You are nearly always tired. After every long rest, you must succeed on a DC 8 + (IE) Constitution saving throw, or you do not benefit from the rest, regardless of the amount of rest you get. Spending an entire day resting will automatically give you advantage on the Constitution saving throw.

Real-world Examples

Chronic Fatigue Syndrome, Lyme Disease, Fibromyalgia, Lupus, Hypothyroidism, Multiple Sclerosis, Insomnia, Postural Orthostatic Tachycardia Syndrome

Assistive Options

Beginning a long rest three days in a row at roughly the same time grants a +1 bonus to the Constitution saving throws, keeping the pattern adding an additional +1 bonus cumulatively to a maximum of +5. Keeping a diet for at least seven days of fish, vegetables, and nuts gives a +1 bonus to the Constitution saving throw. Drinking more alcohol than (Constitution Bonus) drinks will negate this bonus. A weighted blanket during a short rest also gives a +1 bonus to the Constitution saving throw. Such a blanket can be made from two large animal pelts for a medium humanoid or two medium animal pelts for a small humanoid plus enough sand to make the total weight 10 percent of your body weight. The cost of fabrication is 20 gp.

Magical Assistance

If the fatigue is caused by Insomnia, a Sleep spell or other effect that mimics it will assist in getting to sleep during a long rest and will reduce the IE by 1 Extent until the next long rest.