@peachtreeoath Hey bud, thanks for playing the game and the kind feedback.
The destructible landscape is done by reading in a bitmap image. Anywhere a particular colour becomes the area to walk, anywhere white is indestructible and everywhere else is destructible. Internally you keep track of the current state of each pixel. When an explosion happens, you update the internal structure and manipulate the bitmap to incorporate this new data. You then refresh the background so that it redraws a modified background. As you are using the internal state for collision checks, the character will fall into any gaps.
I worked on Worms Revolution a couple of years back, but I didn't do any landscape coding. I was responsible for all the weapons code :) This game was written from scratch in C++, but we used SDL for the basics.
We did implement all the Lemmings, but then changed the functionality slightly to fit our game and removed the abilities we didn't need.
In our post-jam version we will be adding some different. Haracger abilities to switch things up a bit. We will also changing a few other things to make it less like Lemmings, even though the influence will still be obvious.
Thanks again for playing.