Franko Tildon by Skrux

Franko Tilden is a specialist and therefore great pusher, thanks to his AoE, and scaling damage would be incredibly powerful against tower and mercs.

His trait Need a light? is stacking from all sources, both basic attacks and abilities. The debuff dissappears after X seconds.
Ready to roast is similar to Tychus's Overkill, but it doesn't require target.
Barbeque time drains a mana quickly. Longer Franko stays in one place, the more damage will deal the detonation.
I love the smell of napalm is hard CC.
Perdition turret  has long duration and it's burrowed when no enemy is nearby. There should be some kind of low visibility warning for the enemy team.
If you have trouble understanding the Scorched Earth, imagine forest fire.

I did not gave him any numbers, because it is the matter of balance. There's no point in throwing random numbers. And talents would be the cliche option - reduced mana costs, increased damage, increased damage against nonheroic targets etc. I again don't see point in writing them out.