Shade
Monster Junkie
Sounds good, assuming you mean "Cha" rather than "Wis", since we dropped Wis to 10. And since these are artifacts, we don't have to worry about the troublesome creation bits. 
So...
The Venom Lance: The tip of this +4 lance appears to be a dragon's claw. The haft is covered in green scales. This lawful evil intelligent artifact has Int 18, Wis 10, Cha 18, and Ego X. The venom lance can use detect good at will, can cause fear in an enemy at will, and use water breathing on its wielder 1/day. Additionally, the venom lance can produce a mild venom 3/day. On the next successful melee attack, the venom deals 2 points of Constitution damage (Fortitude DC 24 negates). Like the other Taumet relics, its special purpose is to join with the other relics to form the Taumet. Its special purpose dedicated power allows it to use poison (heightened to 4th level) once per day as a touch attack.
The venom lance has darkvision, blindsense, and hearing to a range of 120 ft.. It can speak Common and communicate telepathically with its wielder, and can read all languages as well as use read magic at will. Caster level 20th.

So...
The Venom Lance: The tip of this +4 lance appears to be a dragon's claw. The haft is covered in green scales. This lawful evil intelligent artifact has Int 18, Wis 10, Cha 18, and Ego X. The venom lance can use detect good at will, can cause fear in an enemy at will, and use water breathing on its wielder 1/day. Additionally, the venom lance can produce a mild venom 3/day. On the next successful melee attack, the venom deals 2 points of Constitution damage (Fortitude DC 24 negates). Like the other Taumet relics, its special purpose is to join with the other relics to form the Taumet. Its special purpose dedicated power allows it to use poison (heightened to 4th level) once per day as a touch attack.
The venom lance has darkvision, blindsense, and hearing to a range of 120 ft.. It can speak Common and communicate telepathically with its wielder, and can read all languages as well as use read magic at will. Caster level 20th.