Repel Potions are a type of Potions that will grant semi-permanent immunity from facing one Monster of your choice. After drinking the potion, you can select one monster from one of the three Areas that the Repel Potion works for that you will no longer have a chance of encountering in Combat. There is no time limit on this effect and it will only be cleared if you decide to by clicking on the Notification or by drinking another Repel Potion to choose a different monster to repel. There are currently two types of Repel Potion, Small and Large, which work for three different areas. The effect of Repel Potions do not stack (e.g., a Large Repel Potion will override a Small Repel Potion and vice versa), so only one Monster in total can be repelled at a time.
The Repel Potion, also called the Small Repel Potion, can be made with Level 20 Brewing from 1 Small Vial, 1 Strange Leaf, and 50 Red Mushrooms. It can be used to repel a single Monster from either the Fields, Forest, or Caves. A common target is the Bear so that Skeletons can be more efficiently fought in the Caves.
Large Repel Potion
The Large Repel Potion can be made with Level 53 Brewing from 1 Large Vial, 5 Strange Leaves and 300 Red Mushrooms. It can be used to repel a single Monster from the Lava Dungeon, Northern Fields, or Cemetery. A common target is the Ghost so that Reapers can be more efficiently fought in the Cemetery.
Huge Repel Potion
The Huge Repel Potion has not yet been released, but likely will after Huge Vials are released. It will likely be able to repel Monsters from the Ocean, Castle Dungeon, and the next unreleased Combat Area.