4.20 Kogmaw's corpse blocks cursor interaction and causes collision.
Short Story: Kogmaw's fully dead corpse has collision and a bigger area where you can't right-click move.
Long Story:
I was playing a Player VS AI to check out the new 4.20 and was against Kogmaw, ashe, Cass, J4 and a WW (not sure if the other 4 are even really relevant), my team consisted of Varus (me), Kalista, Chogath, Lulu and Irelia. ANYWAY::: As I was playing I began to notice a wierd issues with my pathing because I would be trying to click to go somewhere (as in somewhere around kogmaws corpse area, but im not really paying attention at first, because why do I need to know where his corpse is right?). After awhile, I notice when I was trying to move later on, I couldn't see the "move here" symbol (whatever the legal term is). Later on in the match after I killed kogmaw I checked and confirmed it was a pretty sizeable area, his collision area where his corpse is, is about the size of a cannon minion and the area which I can't click is about 3-4 times that size. I didn't notice any issues with the other corpses but may pose an issue with Zyra since they have similar passives.