The Mega-Supreme Potent Energy is a 'harvestable' and a consumable that was introduced during the Ratboy's Nightmare Update. It is one of the many collectibles that are needed by the players in order to complete the entries of the Itempedia of the Nightmare. Valid ways of acquiring the Mega-Supreme Potent Energy include the following:
- A possible drop from the Goons.
- A possible serving served from The Deli's waits.
- On props, objects, and furniture in The Back Area.
- On aisle shelves, props, and objects in The Supermarket.
In appearance, the Mega-Supreme Potent Energy is a tall red-and-yellow can with distinctive designs and patterns on the energy drink. It is sealed with a white plastic lid, as well as imprinted with a square-patterned design and a light-beam indicator at the center of the energy drink.
The Mega-Supreme Potent Energy can be used and consumed by the players to restore 10 HP back to the players' health pools. In addition, the players will receive 10 extra stamina points, enabling the players to attack and/or escape from threats if their stamina bar is low.
This does not increase the maximum stamina pt. capacity from 10 to 20, but acts as an 'emergency backup' if the player is in danger. Along with the restoration of 10 stamina points, the players will also receive 5 walkspeed points for approximately 45 seconds, increasing their speed. Its walkspeed effect can be stacked on top of each other, making the player faster for a longer duration.
- The Mega-Supreme Potent Energy is often used in places such as The Road and the End of the Road, to quickly travel from one end to another at a quicker pace.
- The Mega-Supreme Potent Energy is one of the first consumables in Fantastic Frontier that uses the term 'Energy' instead of 'Stamina.'
- They are fairly common throughout The Supermarket in the Nightmare.