With the new zombie AI apart from other things we will be also changing how theirs attacks are working. Knocking player down after jump or heavy attack is on the list, player will not be pinned to the ground but he will still be able to fully control the character - crawl away, roll out or stand up or even fight back from the ground.
Injured animations for broken limbs are planned also with visualization of splint on it.
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With broken limbs your speed and ability to do some actions will be limited to some extent.