'The yelling won't stop': Yellies, the toy that is triggered by the shrieks of children, is debuting new characters after explosive holiday sales

Hollis Johnson/Business Insider

Yellies' sales tripled over the holiday season.

• New Yellies characters are hitting shelves in 2019, as Lizards and Bunnies join the "Spooders." 
• Many people were disturbed or confused by the idea of Yellies, which have the tagline: "The louder you yell, the faster they go." 
• Despite some backlash, the toys are a hit, with sales tripling over the holiday season and selling out at certain retailers. 

New Yellies characters are hitting shelves after viral success and an explosive holiday sales season. 

Hasbro is debuting new Lizard Yellies this month, followed by Bunnies in March, the maker of the controversial toy told Business Insider.

Yellies quickly gained both fame and infamy with the arachnid-esque "Spooders" in 2018. The basic concept: The louder kids yell, the faster the Yellies scoot.

Read more: People are freaking out about a toy that chases kids faster the louder they yell and 'feeds off of screams of terror'

Many people were perplexed and disturbed by the concept. After all, giving a child a toy that requires yelling - specifically, yelling at increasingly aggressive volumes - seems like a declaration of war against anyone trying to enjoy a quiet, peaceful Christmas.

"Who on earth thought inventing this toy would be a good idea?!" Karen Alpert, the writer behind the parenting blog Baby Sideburns, said on Facebook.

Business Insider had a chance to try out the Yellies before they hit shelves. Here is what to expect from the new Yellies: