Dagger of the Serpent (3.5e Equipment)

Dagger of the Serpent
The Dagger of the Serpent appears as a kris with a 6-inch-long blade. The crossguards look like serpents, and the serpent eyes are rubies that glow with a piercing red light.

This artifact's power is matched only by its extreme danger. In its basic form, which is revealed by an identify spell, the artifact appears to be a weapon with an enhancement bonus equal to 1⁄3 your character level. However, it does not strike the physical -- it strikes at the soul instead. Any creature struck with this weapon must make a Will save (DC 10 + 1⁄2 character level + Charisma modifier) or die. If the save is successful, the creature takes no damage. If you are not using Charisma in your game, replace this with Intelligence.

That alone would make it a powerful artifact prized by many, but the Dagger is substantially more sinister. It is actually intelligent, and casts spells as a Sorcerer with a caster level equal to two less than the wielder's character level. It has mental ability scores equal to its wielder's or 30, whichever is higher. What makes it so dangerous is that the Dagger will attempt to dominate any wielder.

If the wielder is not an arcane spellcaster, they must make a DC 30 Will save every round or the hand holding the dagger will turn around and stab the wielder (forcing them to make the normal save or die). Should they die from this, their soul will be sent to the plane of Maladomini. If the wielder is an arcane spellcaster, however, the Dagger will attempt to dominate the wielder. The wielder must instantly make a DC 30 Will save or the dagger permanently controls the wielder until the dagger is removed from the wielder's person and a remove curse, greater restoration, wish, or miracle spell is cast. Should the wielder make the save, the Dagger will attack the wielder with every spell it is capable of. If the wielder dies in this assault their soul will be sent to Maladomini, but should the wielder manage to exhaust the Dagger of spells they permanently dominate the Dagger instead and unlock its full set of powers.

All of the Dagger's powers are operated by the stat the wielder uses for his spellcasting DCs, including the aforementioned save-or-die power. In addition, the hit and damage rolls made by the dagger are made with the same stat, not Strength.

The Dagger has a minimum character level of 15. This means that whenever "character level" is mentioned, the minimum such level in any calculations is 15.

Powers
As previously mentioned, the Dagger forces every opponent damaged with the weapon to make a Will save or die. Also as previously mentioned, it casts spells as a Sorcerer with level equal to two less than your character level.

The Dagger allows you to counter spells by cutting the threads of magic that create them. This works as the normal Better Counterspelling but allows you to counter any spell you can see, not just spells in your threatened area. You can end any ongoing spell, spell-like, or supernatural effect by hitting it with the dagger and making a damage roll against the caster level of the effect (supernatural effects have an effective caster level equal to the hit dice of the creature that created them).

Perhaps the greatest power of the Dagger, however, is the manipulation you can do to the souls of others. By killing with the dagger's save-or-die property and making a Will save of DC equal to 10 + the challenge rating of the creature killed, you can graft your own soul threads onto the body of the killed creature. This works like a true mind switch, except the new body is your new natural body, the creature does not take over your old body (instead it dies), and you gain all the supernatural and spell-like abilities of the new body. You also gain the hit dice of the new body, but not any of the class features; you retain your old class features and continue advancement as normal. If you fail the will save you fail to graft your own severed soul, and your soul goes to the plane of Maladomini.

Further manipulation of the soul may be possible. With special technique in cutting and grafting you may be able to retain pieces of the souls of others, for example giving you their class features or gaining the new form as an Alternate Form, but the Will save for that would be much higher. Once an archmage with this ability used it sever his own soul and, instead of being sent to the plane of Maladomini, made himself a Suel Lich. It is recommended that the DM carefully watches this and the other soul-manipulation ability, and perhaps use it once or twice as a power-up effect for a character or party of characters. Each time foreign souls are grafted with your own the Will save greatly increases.

To use any of these powers, the wielder must first know of them and, normally, the Dagger will not tell the wielder. A Knowledge (Arcana) and Knowledge (The Planes) check, DC 40, will tell the wielder of every power except the soul manipulation powers; for that, a Knowledge (Arcana) and Knowledge (The Planes) check of DC 50 is required.

Legend
Not much of the world outside of the academic world and wizard world, which often overlap, has ever heard of the Dagger of the Serpent. Those that have know it as a powerful weapon that is incredibly dangerous to its wielder and leave it at that. Some that understand its power call it the Serpent because of its look and its ability to cut at the very soul of magic &mdash; reminiscent of an ancient personification of magic.

The truth is, the Dagger was created by the archdevil Baalzebul after, scholars say, he was cursed into his permanent form as the slug or the serpent (the scholars can never seem to agree), and that is where the weapon's name originates. It was created to help him get around the limitations of his form and perhaps even take a new one. Maybe he used it to permanently take a new form and discarded it; maybe the treachery against Asmodeus was discovered and it was cast out; or perhaps it still remains in his fortress on the layer of Maladomini in the Nine Hells of Baator.

Plot Hook
The Dagger actually did come to the Prime Material Plane. Baalzebul successfully used it to take on a new form, and afterward sent it to the Prime in the hope of using it to both sway worthy archmages to his cause and winnow out the unworthy.

Right now, however, it's not doing that. It's being held in the manor of a wealthy collector of artistic works who knows of some of its more minor properties but none of its more sinister ones.