Nightmare Fuel

Nightmare Fuel is a Refined Magic Item in Don't Starve. It requires a Prestihatitator to prototype and costs 4 Dark Petals to craft. It can also be obtained as a drop from various mobs and objects.

Mobs that drop Nightmare Fuel includes:
 * Beardlings
 * Crawling Horrors
 * Damaged Clockworks
 * Splumonkeys (and Shadow Splumonkeys)
 * Terrorbeaks
 * Reanimated Skeleton

Objects that drop Nightmare Fuel include:
 * Ancient Statues - when mined with a Pickaxe
 * Graves - when dug using a Shovel
 * Ornate Chests (25% chance) & Large Ornate Chests (75% chance)
 * Touch Stone - when resurrected

Nightmare Fuel is used to craft Magic items. It is also used to fuel Night Lights and Maxwell's Codex Umbra (to summon Shadow Puppets). Chester can transform into Shadow Chester by placing Nightmare Fuel in each of his nine inventory slots on a Full Moon.

Gathering
If a character's Sanity decreases below 40% of their maximum (80 for most characters, 60 for Wes, 48 for Willow, 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 yet rewarding 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, which can yield what is probably the most Nightmare Fuel at one time.

Downloadable Content
In the Shipwrecked DLC, Nightmare Fuel can also be acquired by gambling at the Slot Machine, by hammering Wildbore Heads during a Full Moon, or by killing Crabbit Beardlings while insane.

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.
 * When dropped on the ground, Nightmare Fuel appears as pulsing goo.
 * Although Beardlings will drop this, Beardlords will not.
 * 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.
 * According to Webber, Nightmare Fuel feels cold. However, according to Willow, Nightmare Fuel feels warm. This may indecate it has different properties to different people, most likely relating to what the person finds scary.

Gallery
Koszmarne paliwo