GameStop (GME) stock soared as much as 80% Monday and was halted for volatility after "Roaring Kitty," the person who is seen as the kickstarter of the meme stock frenzy during the pandemic, posted online for the first time since 2021.

"Roaring Kitty," who was identified that year as Keith Gill, became a prominent figure on Wall Street Bets and YouTube for his bullish stance on GameStop (GME).

Sunday's post on X included a meme of a video gamer leaning forward, appearing to take the game seriously. The last time Roaring Kitty posted on X was in June 2021.

Gill was known for posting videos about why GameStop was poised to go higher and ended up testifying before Congress about the massive January 2021 short squeeze spurred by an army of retail traders.

Monday's gains follows a recent rally in meme related stocks. Theater chain operator AMC (AMC) gained 19% during the session.

As Yahoo Finance’s Jared Blikre recently noted, the recent meme stock surge doesn't appear to be the ominous signal it has been in the past, but rather a healthy risk appetite for investments.

Ines Ferre is a senior business reporter for Yahoo Finance. Follow her on Twitter at @ines_ferre.