Grimacing monsters with long twisted horns and rattling chains, tearful children, lots of artfully swirling fire—D.C.’s Krampusnacht is not a typical Christmas celebration, but it just might be the most fun.

Now in its fifth year, D.C.’s annual Krampusnacht (Krampus Night) not only lets residents get weird but also does good, serving as the largest fundraiser for a local charity Santa’s Cause DC which buys school supplies and presents for foster kids.

“It started off with us watching videos from the European Krampuslaufs [Krampus runs] and realizing that with the group we had and our love of costuming and this kind of stuff, that we wanted to try to do something here,” says Michael Clay, one of the original Krampusnacht organizers. “We paired with Santa’s Cause because we thought ‘let’s see how it goes and at least we’re doing something for good as well as fun.'”

Rooted in Austro-Bavarian Alpine legend, Krampus is a sinister companion of Saint Nicholas. Rather than rewarding nice children with gifts, the dark horned figure described as half goat, half man punishes the naughty ones.

“We all know the story of kids getting coal in their stockings and I mean if coal is the worst you can get, like, really? I think the Barvarian cultures had it right in that you should be a little scared. But Krampus wasn’t about just being a punisher, he was also this reference point of ‘you’ve been bad, but you can still do good,'” Clay said. “I don’t really think Krampus is this evil thing, he’s more of a balancing force for the good.”

Hundreds of revelers kicked the night off around 5 p.m. on Saturday with a family-friendly party that included traditional European dancers and fire performers. Mischievous Krampuses (some with intricately crafted masks) ribbed adults and kids alike, but kindly elves were on hand to assuage any genuinely frightened youngsters.

“I’ve made so many children cry,” one Krampus laughed to me after she growled at a passer-by. “But I try to walk away before cracking up.”

The party was followed by a high-spirited march down H Street, led by local all-women’s drumming group Batala. Krampuses lurked at restaurant windows and snuck up behind unsuspecting pedestrians, Saint Nicholas slipped people candy canes, and bemused bar goers snapped selfies.

“When [the Krampusnacht DC founders] had the idea to bring the Krampus tradition into the D.C. area, [my husband and I] were obviously the go-to for Mr. and Mrs. Claus,” said Jules Kendrick, who cofounded Santa’s Cause DC with her husband Piers Lamb. “We actually had not heard about Krampusnacht until they told us about it. We went home and did a bunch of research and were instantly in love…it’s a lot of fun but it also does a lot of good for the community.”

The event terminated with an after party, intended for adults who wished to relax after a long night of scaring children and to continue to make merry in their Krampus regalia.

“It’s a really great partnership, and it ensures that the kids in care get the presents they want at Christmas,” said social worker Jake Klauss, talking about Krampusnacht, Santa’s Cause DC, and Family Matters of Greater Washington. He said all of the approximately sixty children in foster care receive gifts. “It helps me get into the spirit of Christmas every year to do this.”