Worms 3D is definitely full 3D. I own it.

And to be honest with you, I prefer the 2D games. The third axis makes some of the more skilled shots near impossible to make, and so there was always a bigger reliance on hitscan, melee and homing weapons. Which isn't as fun imho.

The latest 2D one has weapon crafting and vehicles, which feel a bit odd, but otherwise it's pretty faithful to Armageddon, the most famous 2D version.