To feel the effect of Royal Potion you need to be enlisted in Fish Hunt or Gold Hunt Royal Contest (We run it weekly).
1 Royal Potion gives you 5 charges.
Each charge boosts your Royal points when you catch a fish or collect a coin for 10 additional Royal Points.
POTIONS ARE STACKABLE
You can drink potion after potion to stack them up.
When you get over 100 stacked charges (20 potions) you get 100 Additional Royal Points per cast or collected coin and it takes 10 potions from your inventory.
Next milestone is at 500 stacked charges (100 drank potions) and 1000 stacked charges (200 potions).
Stacking potions lets you increase the consumption and helps you gain more royal points in the same amount of time.