Leg Weakness
Your legs get weak due to muscle tone or neurological failure. This reduces your movement speed by (IE) × 25 percent without assistance. Consider the Strength attribute to be (IE) × 3 less for all Strength checks involving leg strength. Every round spent standing requires a successful DC 8 + (IE) Constitution check, the DC increasing by +(IE) each round. Failure results in you immediately needing to sit or be prone.
Real-world Examples
Slipped Disc, Guillain-Barré Syndrome, Multiple Sclerosis, Peripheral Neuropathy, Parkinson’s Disease, Myasthenia Gravis, Amyotrophic Lateral Sclerosis, Down Syndrome
Assistive Options
Braces, wheelchairs, or other mobility devices are helpful. Leg braces reduce the IE by 1 while worn but must be removed during long rests to gain the benefits of the rest. Adding crutches with the braces reduces the IE by an additional 1 but must be held to move during combat, requiring creative attack strategies.