You will note that Teclis has two profiles instead of the normal one. Which profile you use depends on which of the potions Teclis drank last. He only takes one draught of each potion with him to battle, so you can only use each type once.

At the start of the battle, Teclis will be under the effects of the potion of Sariour. At any time he may choose to drink the potion of Charoi.

Note, however, that the number of Wounds on the profiles refers to starting Wounds. For example, if Teclis suffers a wound before he drinks Charoi then he will not go back to 3 Wounds when he does so.