I would suggest deciding how it is attached inside and how it is deployed, that might lead you to concepts regarding physical attributes and complications ie:
*is it coiled in his stomach...if so what happens when he eats etc
*How is it deployed? through a flap? In one loop or sections? (as in one of spidermans' villans Dr octopus) does he swing it around like a mace or does it strangle like a python? (or both)

Is it an intert object or is it alive? does that work with or against your warrior?

*what weaknesses do your decisions infer? Water & Rust? does he sink in water? does it need maintinence? Can it be rendered ineffective by magnetism? These all add a twist like Kryptonite that gives your game a bir o f spice...smile

Also in mention to the back story, is it a weapon he has had inerted (voluntary/involuntry) or was he born with it?

What training did he get to use it ie: military so he is profficent and effective, or taught himself os he is rahter erratic but effictive.

I would say use a program you are familiar with to start with and explore from there.

have fun.
Boofy