When i play a zvz I make an oversier (could be used with overloard speed) and just hot key the oversier with my main army. (i usually make 2 or 3 as the game progresses)
I then rally all my hatcheries to it. If in a battle and dont wanna be going back and forth grabbing the reinforcements they come right to my army no matter where it is.
Yes it gets picked off from time to time by fungals or hydras but most of the time it goes un checked by the other player. This is also great for keeping tabs on player 2's army early in the game. just have an oversier following a roach around and itll hover over their main army.
works great in pvz and tvz as well. if your facing a mainly ling/roach army. just have a unit follow around the main army, medivac/viking/phenox/obs/warp prizm (obs is kinda too slow but still works for a while) not sure why i dont see this more often
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