This should not be a thing right?

Spiders can climb walls very quickly

Sadly the video is too big to upload with 10MB limit not suprised.

But...
https://www.youtube.com/watch?v=K-B3cbaPV7c

BTW if you think the glass and blocks look strange it is just cause I was using Faithful(Texture Pack)

NOTE: I was on a private multiplayer server