Omg! I had a project with difforent layers, I wanted lower layers to be cancelled for the player that is moving around, yet stay active for lower layers that enemies are walking around on.
I'm example. Player layer=3 blocks layer=3 set solid. Blocks <layer 3 set solid disabled (enemies then walk wherever on their layer)
Summery: a disable solid instance for a set variable/layer
So multiple layers can have difforent objects to avoid.
I can make a 2d 3d game if this was implimented!
It could also solve the stair case issue...or whatever