Nice mechanic really well executed and presented :)
I think, like a few others said, that there’s an iteration on this where the web catches flies that fly into it, but - maybe - flies can escape after 10 seconds, breaking the node they’re forming; keeping the risk/reward by adding a bit more motivation to building a web.
That said, I had a lot of fun as it is- and 48 hours is a short time to make a game- so what do I know :D