Fear is the secret to happy marriages, lasting friendships, and the final ingredient in numerous madman-created serums. Take advantage of this versatile additive with today’s Groupon: for $10, you get two tickets (a $20 value) to The Shadow’s Edge Haunted House, located in Mangelsen’s parking lot off of I-80. The Shadow’s Edge is open September 24–26, and every night in October. On Friday and Saturdays, the house is open from dusk until 12:30 a.m.; on weekdays, it closes at 10 p.m.

For the past eight years, The Shadow’s Edge has been shocking its visitors with high-quality chills, jolts, and disembodied shrieks while providing a seasonal home for the area’s orphaned undead and roaming reanimated. The 2010 season includes new rooms and an updated, 8,000-square-foot floor plan, so ghost-hunters who memorized last year’s layout in an effort to scare the house’s inhabitants will be as in-the-dark as first-time guests. As you traverse the halls of the cursed abode, expect evil clowns, brain-hungry zombies, and skeletons, bitter after losing their skin in a mishap with pop rocks and an industrial vat of liquid nitrogen. All of The Shadow’s Edge creatures were created with professional special effects, so nearly all of your senses will be bombarded by the house’s fully-realized harbingers of total-body horror.

There are more than 15 rooms in The Shadow’s Edge, connected by a series of labyrinthine hallways that make asking for directions even more of an exercise in futility than it is at unhelpful gas stations, which are, by nature, haunted. Ideal for fearless pairs of best pals or ghoul families who’ve just moved into the neighborhood and have no one to bond with, The Shadow’s Edge Haunted House injects cherished seasonal scares into the surrounding scare-free community.