Nightmare Fuel

"All of my fears in liquid form."

- Woodie

Nightmare Fuel is a Refined Item crafted with 4 Dark Petals. A Prestihatitator is required to unlock the recipe. It is also dropped by Beardlings, Crawling Horrors, Terrorbeaks, damaged Clockwork Monsters, and Splumonkeys. It can also be acquired when a Touch Stone breaks and by mining Ancient Statues. It has a slim chance to be dug up from Graves, 25% chance to be found in Ornate Chests, and 75% chance to be found in Large Ornate Chests.

In addition to being able to fuel Night Lights, Nightmare Fuel is used to craft several Magic items. Nightmare Fuel is also use to fuel the Codex Umbra, transform Chester into Shadow Chester, and make Shadow Puppets.

Gathering
If a character's Sanity decreases below 40% of their maximum (80 for most characters, 60 for Wes, and varies for WX-78 based on the upgrade level), all Rabbits change into Beardlings and can be killed to gather Nightmare Fuel (along with Monster Meat and Beard Hair). An easy way to do this is by trapping a large number of Rabbits and then lowering Sanity to below 40%, after which they can all be murdered all at once while in inventory. However, be careful, as this is liable to trigger the Krampus by advancing the player's naughtiness level beyond the threshold.

Alternatively, Nightmare Fuel can be acquired by killing Crawling Horrors and Terrorbeaks. Crawling Horrors are easier to deal with than Terrorbeaks; the latter don't appear until Sanity is very, very low, so it's possible to kill Crawling Horrors one at a time.

A safer and simpler way to get Nightmare Fuel is to capture Bees with a Bug Net and then release them at an Evil Flower patch, which can be found where the Things and Maxwell's Door are. This will eventually cause more Evil Flowers to spawn, and their petals can be crafted into Nightmare Fuel.

The most dangerous way is to venture into a Ruins or Cave and find a location with Nightmare Lights and Nightmare Fissures. When the Nightmare Cycle ends, all of the Shadow Creatures that spawned from the Lights and Fissures will die and drop Nightmare Fuel.

Trivia

 * The term "nightmare fuel" is a common phrase on the Internet used to describe works of fiction, or scenes therein, that are extremely likely to disturb and/or frighten the audience.
 * Although Beardlings will drop this, Beardlords will not.
 * When dropped on the ground, Nightmare Fuel appears as pulsing goo.
 * Maxwell, upon examining the Ancient Guardian, says "My my, the fuel has changed you." This implies that prolonged exposure to Nightmare Fuel can alter creatures in some significant way.

Gallery
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