The itsy bitsy spider sings a song, A song that goes something likes this: This morning when I was hardly awake, Here comes a punch in the face, But now you are trapped in my web, Let's hope we don't all go mad.
I'd hardly call anything the Bible of our times» special thanks to MagicManICT I only logged in to say this sentence. by neeco » 30 Oct 2018, 02:57 Default Client, Best Client!
It's totally random. You can even find webs and spiders from the water. However, if your inventory would overflow, I think these finds are prevented from generating in the same way as excess cattails rather than falling to the ground.
I'm 99% sure that spider/web can proc when you have full inventory, and it will simply be dropped to the ground. Spiders dropped on ground get run around freely so keep that in mind if you're specifically after them.