From Garry's Mod
Sets the health of the entity.
New health value.
Sets the entity's health to their maximum health.
Entity( 1 ):SetHealth( Entity( 1 ):GetMaxHealth() )
The entity's health is now full.
Deducts 50 points of health from the entity.
Entity( 1 ):SetHealth( Entity( 1 ):Health() - 50 )
The entity now has 50 less health.