GameStop and AMC are both seeing gains in the neighborhood of 20% as of 11:15 a.m. ET—and trading on GameStop shares have been halted multiple times today because of volatility.

At one point earlier in the day, GameStop was up 30%.

It’s a resurgence for the two companies, which were the biggest darling of the r/wallstreetbets forum on Reddit last year. Both companies have seen their share prices tumble from the “to the moon” peaks of 2021, and that has once again caught the interest of short-sellers.

Quoting FactSet, CNBC reports AMC has short interest of 19.5% and GameStop’s level is currently 21.4%.

That has seemingly once again brought out the self-described “Ape” traders on Reddit, who celebrated the gains and urged each other to continue buying once again in threads with titles like “Once more unto the breach, dear friends, once more. The last YOLO.”

“Away we go boys,” wrote user outtathesky_fellapie.

“They called us dead in the water, I think not,” added Then-Display-1600.

r/WallStreetBets was behind January’s explosive growth in GameStop shares, as well as notable gains in AMC, Bed Bath & Beyond, and other companies that were in decline for much of 2020. Massive buying by individual investors created a so-called short squeeze, which occurs when short-sellers—who bet a stock’s price will fall and sell shares they borrowed—have to buy shares in order to exit their positions, pushing the stock upward.