Oak Barrel (previously known as Wooden Barrel) is an S-grade pet. This pet is capable of generating energetic potions which, apart from adding 30 energy (which is the highest energy potion from a pet),speed the cookie up by just a bit and also reduce any damage income the cookie might have from hitting obstacles.
It produces Potions with over-ripened grapes at regular intervals. (When the Juicy Potion is taken, some energy is recovered and because the cookie gets a little bit excited because of the overwhelming flavour of the juice, it makes them sprint. It also decreases energy loss when hitting obstacles.)
This Wooden Barrel full of juice made out of over-ripeneded grapes was left forgotten in a dark corner of the Witch's kitchen and it was able to age into a delightfully sweet nectar with a delicate woody note. You might be tempted to drink the whole thing, but the recommended amount is 1 or 2 glasses per day.