(WARNING: Long and extremely in-depth post!! But read anyway please

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I think it would be really neat if PS had an anti-hero army that players would constantly be in combat with, and what better way to do that than have players on both sides!
I realize that the concept of going to hell and working your way out is already implemented, but I really think it should be more than that. If you die and make it back, players should get the option (or better yet, forced after they die too many times) to become an undead creature. The undead can pvp as though they were creatures, and the same applies to players who see an undead creature, they can just attack it. Also, the undead can only be active in the living plain at night. During the day, they travel as harmless ghosts.
To make things even more tense, the living and the undead cannot communicate to each other.
ZOMBIES will be the starting league for the undead. They have a good toughness but are very slow and stats of your former self influence these set values. (such as if you were a quick theif before, you\'d be fast for a zombie, but still overall slow). The zombies will have it tough on purpose and need a lot more experience than normal in order to improve (ill explain why later). This will cause the undead to attack and maime anything that moves for experience, much like crazed zombies do in real life. Related post on killing:
http://www.planeshift3d.com/wbboard/thread.php?threadid=7582&boardid=11&styleid=3&sid=6133bacadfc113812ba961f40a0e106cOnce zombies have become powerful enough, they have the option to proceed and advance in one of two different undead leagues, PLAGUE BEARERS and SKULLS.
-PLAGUE BEARERS are meaner zombies. They hit lighter and can take more damage, but they can infect others! This would cause the player or creature that was hit to be barely damaged at all during the blow, but instead, the damage speads itself out along the course of time, draining the life. Eventually, the damage would be greater overall. These plagues can be healed easily by healers, that is, if one is around.
OGRES are advanced plague bearers that specialize in poison spells and diseases that they can project in a cloud that can infect more than one target. Ogres also will have the best toughness in the game, able to take just about any blows.
-SKULLS are those skeletons you see in every RPG. The difference between them and zombies is that skulls can equip weapons and light armor. However, they are highly vulnerable to magic, especially healing spells.
UNDEAD NECROMANCERS are advanced skeletons that use the magic of the necromatic dark way. The difference between them and living necromancers are that the undead are far more powerful with their magic and especially in summoning undead npcs. However, they keep the same defenses that a normal skull has.
SHADES are very dark and sinister skulls that obtained an especially evil reputation by doing equal deeds, (Such as a lot of player killing). Shades are cloaked skulls that can travel as shadows and inside others. Thus, making shades the ultimate assassins, but they only work for themselves. Shades can only advance if they kill personal vendettas, such as someone who beat you in a duel a long time ago, or people that used to be in your ignore list.

(Imagine being in some dark alley, when suddenly a shadow moves across the floor, signaling that a shade is nearby. Indeed, it is one, but he is not after you, but with someone you travel with. Creepy huh?) Shades can only be killed by spells and serve unknowingly to the grand shade himself, the Grim Reaper. (maybe)
And now the good part
-SPAWNS are those who made an enormous accomplishment as an ogre, undead necromancer, or shade that has brought them back to the living. Not only have you returned as your old character, but you keep some of the abilities you used to have during your dead life! Such as shade spawns can still travel in shadows, or ogre spawns have an incredible resistance to everything, or undead necromancer spawns have an awesome advantage in their magical abilities!
I dont have any idea how to handle the death of an undead creature, but maybe it would be a good idea to switch between the dead and the living every time you die.
And I think that concludes my long wish. Its extreme, but I still think its a good concept.