Sharn(4HD)+5LA, Whatever 11, keep your alignment CN, fight with a quiver full of lawful arrows as an improvised weapon, take a negative level for each arrow
if you have enough lawful arrows(15), die and have fun sucking as a wight with none of your previous abilities
From K's Revised Necromancer Handbook:
[spoiler]"Hand People Unholy Arrows
Unholy Arrows are very modestly priced. They cost about 361 GP each. And any Good aligned character takes an actual negative level if they hold it in their hand. A character can wield however many arrows happen to be in their quiver, so they can potentially get a lot of negative levels. Any character with negative levels equal to their hit dice dies and rises as a Wight, and the arrows are not consumed in the process. Repeat with Holy, Lawful, or Chaotic arrows as desired."[/spoiler]
now Wights are lawful evil, so get rid of those lawful arrows and get the 3 "good" arrows out of your backpack, now use them in a quiver as an improvised weapon
now you get the tasty "bonuses" from 3 additional negative levels
-3 on all skill checks and ability checks
-3 on all attack rolls and saving throws
-15 hit points
-3 "effective" levels(for purposes of HD etc...)
was worried about it not being a humanoid but to quote from the DMG 3.5
[spoiler]"A character with negative levels at least equal to her current level, or drained below 1st level, is instantly slain. Depending on the creature that killed her, she may rise the next night as a monster of that kind. If not, she rises as a wight."[/spoiler]
Edit:
[spoiler]use a locked gauntlet so you can't drop your FOUR good arrows in your improvised-weapon-quiver.
Now as soon as you rise as a wight, you are instantly slain and rise the next night as a wight.
Keep doing this forever or until someone steals your quiver, even then, your still just a wight. [/spoiler]