Unconscious

In DDO, player characters and hirelings do not die until they reach -10 hit points or lower. Getting reduced to anywhere from 0 to -9 renders you merely unconscious and dying. If you are dying, you lose 1 hp every ten seconds from blood loss until either you die or you stabilize, in one of three ways:
 * Another character can heal you or grant you temporary hit points with any usual spell, item, or ability. Incapacitated Warforged characters can also be rescued with magical repair. This healing has to offset your negative hit points first. Once you rise to 1 hp or greater, you become conscious again (and stop bleeding).
 * Another character can attempt to use the Heal skill on you. This uses up a healing kit. On a successful skill check, this immediately makes you conscious again and sets your hp to 1. Failure only uses up the kit. Warforged characters must be rescued with repair kits and the Repair skill instead.
 * There is a 10% chance every time you would bleed that you become stable on your own. You must make a die roll of 10 or LOWER. You don't recover instantly, however. There is a brief delay, become conscious with 20% of your maximum hitpoints. Warforged characters and characters with the Diehard feat stabilize automatically, but they still have this delay. A proc from an item with regeneration will also trigger a stabilization.

Incapacitated characters are still vulnerable to attacks and to damage. They can easily die from getting caught in area attacks or from enemies that deliberately keep attacking them once they're down.

An unconscious character cannot move or take any actions (except few rare effects, for example Siberys Spirit Cakes).

Undead characters (Pale Master enhancements) no longer die at 0 hp; they benefit from the same unconsciousness range as living characters.

Extending unconsciousness range

 * Bath House: up to +15
 * Die Harder: up to +15, Barbarian enhancement
 * Don't Count Me Out: +5/10/20, Human or Purple Dragon Knight enhancements
 * Eternal Defender: +250
 * Genius Never Dies!: +1000, Alchemist enhancement
 * Holding On: +40 enhancement bonus
 * Legendary Green Steel items
 * : +100 festive bonus
 * Undying Beacon: Allies affected by your Beacons gain Unconsciousness Range equal to 10x your Favored Soul level.
 * : +65 / +225 enhancement bonus (iirc)
 * Weighty Asset: +100 enhancement bonus (available on / )

Pets only:
 * Don't Count Me Out!: +400 enhancement bonus

See also:
 * Diehard feat: automatically stabilize when you become unconscious
 * Divine Intervention enhancement: When a warded ally is incapacitated, this effect heals the target after a few seconds for 10 to 39 hit points and then fade