The macro created for the «Duels» mode version 1.8.9 allows you to automatically use potions-poti (items that restore the player's health) for yourself. To activate the macro, you need to hold down the corresponding key. It is important to note that potions potions must be in slots 1, 2, 3 and 4, otherwise the macro will not work. 

You need to refine the macro so that it is more unique and meets your requirements.