The Guttermouth Key is a 'monster drop' 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. The Guttermouth Key can be obtained through multiple means that include but are not limited to:
- A possible 'rare' drop from the following mobs:
In appearance, the Guttermouth Key appears to made out of what may be obsidian and/or 'otherworldly' materials outside of the Frontier's world. The key is presumably twisted by the nightmare energies that lurks in the Nightmare.
The Guttermouth Key is mainly used to unlock doors sealed with the keylocks that can only be opened by the Guttermouth Key. These keylocks are made out of the same materials of the Guttermouth Key, being black and obsidian-like. This can be differentiated from other key-locked doors based on the size of the door (most Guttermouth Key-required doors are normal, standard door sizes).
After a player had unlocked and entered a Guttermouth Cell, they may participate in different Guttermouth challenges with different mobs throughout the Nightmare and familiars of the Frontier. After completing a Guttermouth Cell Challenge, players can receive their rewards in the form of a floating, shining treasure chest. One thing that players should keep in mind is that the Guttermouth Key can only be used once, before disappearing from the players' inventories after being used to unlock a Guttermouth Cell.
- The Guttermouth Key is often obtained through the genocides of Boomers, Clown Buggies, and Flying Clowns that have a high spawn-rate in their respective zones. (The Road/The Supermarket)
- The Guttermouth Key is the only key out of its other 'counterparts' that have a selling price above 0 gold.
- It has a 1% chance of being dropped by a Data Mite or a Flying Clown, and a 2% chance of dropping from all other mobs that drop it other than the Democan, which has a 4% chance of dropping it. This makes Democan have the highest chance of dropping the Guttermouth Key.
- The Guttermouth Key is the only key out of its other 'counterparts' that drop upon death.