PSA : Zz'Rot Is Actually Better For The Game Now

Old Zz'Rot : Main reason it was bought was to stall enemy waves and auto-push your minions. Was place-and-forget to the point that you would just put it somewhere then leave it instead of actually working with Zz'Rot to take objectives as intended.

New Zz'Rot : Main reason to be bought is the reason it was originally created, to take objectives with the player. Due to HP remaining the same all game, Voidspawn can no longer perma-freeze enemy minions toward the mid-late game due to being out-scaled damage vs HP. In addition, Voidspawn can no longer walk from your outer Tower to the enemy outer tower, making you have to put it outside of tower range removing its safety to attack the enemy tower. Now players have to actually defend their Zz'Rot due to its lowered safety, the trade up however is tower damage, a lot of tower damage. 2-3 waves of minions is all you need to take a full HP tower down, late game you only need 1 wave if you also have a Banner of Command Cannon Minion.

TLDR : The cancerous stall tactics and under-your-tower safety was heavily nerfed in order for the item to receive a heavy buff allowing it to fulfill its original purpose of killing objectives.