Undead are creatures made from dark energy due to a process known as necromancy. This energy is used in order to bind a soul to the corpse or corpses desired. The soul can only ever be released when the body it is tied to has been "destroyed". The exception to this are ghosts, who are created by traumatic events which force them to remain in a location (example: A ghost of a knight remaining in a castle).
Undead Creation
Undead have 14+1d8 HP
Undead have 2d4+3 CON
Undead have 5 Move
Choose one: Proficient with a weapon or 2 natural weapons that deal 1d6 points of damage each.
Assign these numbers to stats: 10, 8, 6, 4, 2, 1, 0
Immunity: Dark
Weakness: Light
Special Conditions
If Ghost: Con 0 (unaffected by weight), Move is 6 (Flying), STR and DEF are permanently 0 and they have a 0 Growth Rate, and AR/DR/SP are marked as "--", Immunity to Slashing, Bludgeoning, and Piercing
If Zombie: 4 Move, Weakness to Fire
If Lich: Special kill condition, a lich is truly killed when their phylactery is destroyed, otherwise they revive 1d4+1 weeks later. A phylactery has 50 HP, 15 AR, and 6 RR. It has no DR/MR. +2 MAG/RES
If Draco Zombie: Breath Weapon (1d20+Speed, DC 22 to avoid, 3d8+MAG Dark damage, 5 Square line, Costs 2 MP to use). +4 to all stats
If Wraith: Type; Undead, Mounted, and Armored, Immunity to Slashing and Piercing, Weakness to Bludgeoning. +4 STR/DEF