At any time during your turn, you may drink one or more of the Potions you have completed to activate their magical effects. Each Potion is a one-use special power: once a Potion has been drunk, it can’t be drunk again.
To show that a Potion was used, just rotate it upside-down. Then, you can apply its effects.
A - A Completed potion
B - The same potion, after drinking it.
When you use a Potion to take marbles from the Dispenser, you never trigger Explosions - Explosions can only be triggered when you use your regular pick for the turn. In the same way, you don’t trigger Explosions when you use a Little Help from the professor.
Using a Potion does not make you lose the Potion tile: it still counts as a complete Potion, and it’s still worth the same number of points at the end of the game.
You can also drink Potions as soon as you complete them, if you wish. This exam aims to prove your worth as witches and wizards, not to merely test your theoretical knowledge of potions. Being able to make good use of the fruit of your labor and turn it to your advantage is a critical skill!