A limited edition of five designed by Zhang for the Beijing Toy Show, priced at 4,800 yuan, sold out quickly. "I think Chinese toy buyers are a little bit crazy," he said.

Zhang said buyers also love to trade toys on social networks, adding, "They have online chat rooms to show off and exchange them."

With a team of four, including himself, Zhang supervises the painting of his collectibles. He uses social networks such as WeChat and also micro blogs to promote his work. Taking part in various toy shows at home and abroad produces good opportunities to sell and spread news of his work.

Xuan Yilang works as a part-time toy designer, which he said is common among Chinese designers.

He works at a design company in Beijing by day and creates his toys at night. The 30-year-old created two monster-like sculptures in 2015, naming the figures, who have thorns on their heads and backs, Mozzila and Yuki.

"They look very scary and strong. However, they're very kind and soft," Xuan said. Both Mozzila and Yuki are made from vinyl and are hollow.

Xuan started to collect toys in 2007. At the time, designer toys were only popular among small groups in this field. In 2015, he decided to become a part-time designer, and this was when the mainland toy market started to boom.

"The situation (on the mainland) now is very much like Hong Kong's toy market before the financial crisis－very prosperous," he said.