Terrain is randomly blocking people.
Basically, during auto-pathing somewhere, champions are 'snagging' on the terrain, (slightly to fully) immobilizing them with some invisible, nonexistent CC.
.
- I have had it happen to me on many recent occasions - several times it has gotten me killed or prevented me from securing a kill.
- It happens** more often when running by walls** (auto-pathing makes champions cut corners as close as possible), but the ground itself has snagged me also.
- A couple times I have been snagged completely by a wall, and my champion started 'tweaking out' - looking every which-way. This was resolved by right-clicking a few times to move away from the wall.
Is there some hidden feature of league I should be aware of? Is the terrain interactive now or something? :-P