The SignalHubman at the center of the pandemic meme stock craze returned to the social platform X for the first time in three years and has sent prices of some of those stocks surging at the opening bell Monday.

Keith Gill, better known as “Roaring Kitty,” posted an image on Sunday of a man sitting forward in his chair, a meme used by gamers when things are getting serious.

He followed that tweet with a YouTube video from years before saying, “That’s all for now cuz I’m out of breath. FYI here’s a quick 4min video I put together to summarize the $GME bull case.”

GameStop was a video game retailer that in 2021 was struggling as consumers switched rapidly from discs to digital downloads. Gill and those who agreed with him changed the trajectory of a company that appeared to headed for bankruptcy.

At Monday’s opening bell it appeared that Gill had revived that interest as shares of GameStop surged nearly 50%, it’s biggest intraday jump since the meme craze in 2021. Other meme stocks like the theater chain AMC were jolted higher as well.

Gill became a cause célèbre in 2021 after his posts on the Reddit subcategory Wallstreetbets ignited a battle between thousands of smaller retail investors and large hedge funds that were betting heavily against the survival of GameStop, shorting its stock.

The small guys won, at least for a while, driving shares of GameStop up more than 1,000% in 2021, and other meme stocks as well. The struggling movie theater chain AMC jumped 2,300% in the same year.

Those meme stocks surged higher again early Monday.

Shares of GameStop Corp., which have faded steadily since 2021, jumped nearly 70%. AMC Entertainment Holdings Inc. leapt 23%.

Koss Co. a headphone manufacturer, spiked 52% and BlackBerry, the one time dominant smartphone maker, rose 7%. The retailer Bed, Bath & Beyond, another meme stock, sought bankruptcy protection last year.

But some meme stocks including GameStop and AMC had already been climbing higher again, and rapidly.

Shares of GameStop Corp., which have faded steadily since 2021, were already up 57% this month. AMC Entertainment Holdings Inc., had risen 10% over the past 30 days.

Gill, or Roaring Kitty, largely vanished from messaging boards after posting a video in June 2021 of kittens going to sleep.

The story of Roaring Kitty and the meme stock craze was turned into a movie last year called “Dumb Money.”