Edited to add specifics.

As to the "disconnected powers" those all come from psi. Let me state my reasoning, and if still it is believed they simply dont work, then i shall simply not use said powers. I believe that honestly, the only one that is a stretch is summoning magic, but how else would i get a huge a** snake onto the battlefield? Haha! The Aoe effect makes sense when i explain it. I was just under the impression that a cs shouldnt be so detailed. I edited it, and hopefully its better. If not ill add another hider adding reasons and explanations.

Reasoning:
1- Everybody can use psi, and simply needs to practice. Ergo, Jynxs can use psi. The ability is complimentary in that sense to all characters.
2- Psi is credited to control the natural world. The logic is that since everything can effect psi, than psi can affect anything. By controling psi, one can control the air that is releasing it, the earth, etc. psi users generaly have more control than is truly good for them.
3- Psi is the essence of existance. By using psi, one can create, control and destroy. I combined the theories of create and control to explain how he can summon.
4- Aoe effect is used to keep his mud nice, cool, and moiste. He maintains it by using psi to "create" water in the air, and to keep it there.

As per the saliva: He was originally a torturers assistant. It was helpfull 3 years ago, and i never got rid of it. XD