The hottest new toy of 2016 is already sold out.

Spin Master, the company that brought you the Build-a-Bear Workshop and Etch-a-Sketch, is seeing similarly wild success with Hatchimals—furry creatures that actually hatch and develop the more kids play with them. The demand is high even with the $60 price tag, which is about $50 more than the average toy, Bloomberg reports. And despite looking like Hasbro’s Furbies, Spin Master told Bloomberg they were inspired by the unboxing videos many beauty and lifestyle influences post online.

“We thought, ‘Wouldn’t it be cool instead if you opened it, something itself would come out?’ That evolved to the idea of an egg,” James Martin, the company’s senior vice president for marketing, told Bloomberg.

There are two Hatchimals species—Pengualas and Draggles—with three more exclusive to retail giants—Burtles (Walmart), Owlicorns (Toys “R” Us), and Bearakeets (Target). But good luck finding one: The toys have become so popular since Spin Master launched last month that there’s a growing number of waitlists.

 

To save Christmas, Spin Master is flying more Hatchimals in from its factories in Asia, Martin told Bloomberg.

“We made the decision to air-freight in because demand is so extreme,” he said. “We spent two years developing this item, and we really, really want to get it into consumers’ hands.”