Nightmares

 are four different types of NPC during the Treehouse of Horror XXVI Event that gives event and crafting currency to get prizes. They appear on the streets of the Player's Springfield and their Neighbors' Springfields. When the player tap them, they get event currency.

Rewards
There are three different ways to collect rewards:
 * In the player's own town, they reward :
 * 1 S'mores during the first act and 1 crafting currency depending on the type of nightmare.
 * Zombies awarded 1 Brain.
 * Snakes awarded 1 Snake Egg.
 * Bunnies awarded 1 Bunny Ear.
 * Skeletons awarded 1 Bone.
 * With a chance of one Formless Terror was added to the above rewards.
 * In their Friend's Towns, they rewarded 1 event currency and 1 crafting currency for the first 90 actions (1 per action).
 * Sending characters from the youngsters character group (excluding Fallout Boy) to "Make S'mores" on the Spooky Campfire.
 * Non-premium characters rewarded 2 nightmares and 4 event currency.
 * Premium characters (excuding Sherri and Terri) rewarded 4 nightmares and 8 event currency.
 * Sherri and Terri rewarded 8 nightmares and 16 event currency.

Trivia

 * A maximum of 20 nightmares could be found in the player's town at a time.
 * However once the limit was reached, nightmares kept spawning to a bank until a combined total of sixty was reached.
 * Nightmares moved from the bank as soon as the nightmares in Springfield were tapped.
 * The spawn time of the nightmares depended on the level of the Spooky Campfire.

Types
appeared in four types. Each one rewarded one different type of crafting currency; those depended on which one of four youngters were the last one sent to "Tell a Scary Story" on the Spooky Campfire.
 * Martin activates the spawning of Zombies.
 * Lisa activates the spawning of Snakes.
 * Milhouse activates the spawning of Bunnies.
 * Bart activates the spawning of Skeletons.