I seen that after the Tai Bwo Wannai Trio quest, you can get a Rune Spear (kp). I'm guessing kp is a poison, but what does it stand for and how much damage does it do?

It stands for Karambwan poison, which is the octopus fish like thing you catch during the quest. It does the same as Super Poison (6 damage), and KP spears are untradable. If you want to trade it, you need a Cleaning Cloth made from a piece of silk, and Karamja Rum (bought from Karamja Pub)

Oh, ok, thanks.