If you watch Overwatch or Counter-Strike streamers on Twitch, you've probably seen them flicking their mice in precise but erratic movements, chasing a series of circles and sliders across the screen. To get in the zone, they often play osu! , a free, open-source rhythm game that demands fast pinpoint responses along to a song. For instance, former Overwatch League pro Hyeon "EFFECT" Hwang said he plays the game for one hour before matches to warm up his hands.

But right now, there's a competition going on in the osu! community that makes those pro shooter players look like amateurs.

The 1,000pp club is like having The Mountain from Game of Thrones on your middle school football team —WholeWheatPete

Outside of the FPS players who use osu! as a practice tool for reaction time and aim, there's a large, dedicated community wherein osu! is the main challenge. Watching them play is about as thrilling and incomprehensible as watching someone crush a Beatmania song on the hardest difficulty, without missing a note. Largely sectioned off from other areas of competitive gaming, osu! players have been plugging away to reach an ever-growing skill ceiling. Just when the community thinks they've reached the pinnacle of skill, someone breaks past that barrier. That's exactly what happened last week when not one, but two osu! players reached a milestone: the 1,000 performance points score.

"The 1,000pp club is like having The Mountain from Game of Thrones on your middle school football team," 21-year-old osu! player and podcaster Peter "WholeWheatPete" Droz tells me. (Most people playing osu! score in the 100pp to 400pp, he said; after reaching 500pp, the skill gap becomes huge.) "Just the fact someone is able to break a barrier that many people in the community regarded [as] practically impossible is such a historic moment, because it keeps pushing the limits of the game."

For most people, hitting a 1,000pp score will be damn near impossible. Playing osu! is a trial of map reading, timing, precision, and adaptability, all tested by one's ability to click timed circles, sliders, and spinners.

Played by a master, it looks like this: a stylus wielded on a tablet to quickly follow the moving circles and sliders on screen. Left hand on the keyboard, master players are able to tap keys exactly when their cursor meets the circle or slider as they activate it with a stylus or mouse.

Achieving a high score in osu! requires not only memorization of the beats, but the raw, mechanical skill to nail hundreds of lightning quick hand movements and clicks. And it's not like you're keeping that level of skill up for just one or two minutes; One of the 1,000pp records was set on a song more than three minutes long, but the other required a 99 percent accuracy rating for nearly seven minutes. Osu! rates players with grades; SS for 100 percent accuracy, down to D for less than 75 percent accuracy. You tally up more points based on how precisely you hit each beat, and the performance is calculated after the game based on map difficulty, mods used, combos made, and, of course, accuracy.

Popular osu! player and streamer Vaxei, who is 15 years old, was the first to reach the 1,000pp score on a map that prioritized speed and agility. And then less than 24 hours later, as spotted by esports insider Rod "Slasher" Breslau, 18-year-old osu! player Caleb "idke" Yin broke the 1,000pp mark on a different map, reaching that score for his timing and precision.

Maps in osu! are created by the community and posted online for free. There are a few different modes: The more competitive mode is osu!standard, but there's also osu!taiko, osu!catch, and osu!mania. Each is a variation on a different rhythm-based game, but the main one is essentially an iteration of a Nintendo DS game called Osu! Tatakae! Ouendan, which was published in 2005. (The English "spiritual sequel" to Osu! Tatakae! Ouendan is called Elite Beat Agents, published by Nintendo in 2006.)

"Years ago, people used to joke about 1,000pp scores because they thought it was impossible," says Vaxei, who first set a record last week. "Achieving a 1,000pp score for me took many years of consistent practice and thousands of hours put into the game."

Vaxei, who's been playing osu! since he was 10, specializes in speed play; he uses a mod of the game called "double time" to speed up songs, WholeWheatPete tells me. His competitor idke has a different style. A player like idke, who excels in accuracy, uses the "hard rock" mod to decrease the circle size, making it harder to hit—unless you're super accurate like idke is, WholeWheatPete says.

osu! being played at a more reasonable pace.

Mods make their super high scores possible. WholeWheatPete says that the highest score on an osu! map without a mod doesn't come close to the possible performance points on modded maps. The mods aren't necessarily making it easier to get higher scores, just raising the skill ceiling—"maximiz[ing] a map's ability to get the most performance points out of it," he said. So a double time mod, like the one used by Vaxei, will get lots of performance points out of a shorter song, but it doesn't make it easy.

Both players use tablets to play osu! to increase precision: Vaxei uses a Wacom tablet and idke uses a Turcom TS-6610. Both are tablets used primarily for drawing, but osu! is one of the few games where the tablet is preferable to a mouse. (There are a bunch of videos on YouTube where players try playing other games on a tablet as a novelty, though. Or, you know, a DDR pad .)

Rivalries are rife in osu!, but sometimes they're more with yourself than others.

"Most players use a tablet," Vaxei says. "The reason for this is that a tablet has absolute positioning on its surface area, unlike the mouse. With a mouse, mouse drift can happen where certain patterns cause your mouse to move in a direction away from where it started on the mousepad."

But that doesn't mean mouse players on osu! can't be successful. Vaxei and idke both say there are plenty of high-level players that use a mouse. And that's part of the appeal of osu! in general. There are a lot of ways to play, plenty of different ways to excel and be the best at what you do.

"Since osu! is a game with a diverse amount of skills, the way [Vaxei and I] achieved our 1,000pp scores are completely different," idke says. "We both have mutual respect for each other for achieving a 1,000pp score in our own way. Though I cannot speak for how Vaxei felt when he achieved the number one spot on the global leaderboard and achieved a 1,000pp score, many people including myself in the osu! community were extremely proud of him. As for the pp record, I didn't expect to immediately beat it within 24 hours of his score."

For idke, aiming for that high score was a personal achievement—not necessarily to surpass Vaxei. But that doesn't mean there isn't a rivalry. Both say there definitely is, but it's not based on the desire to beat the other player at their own skill. (Again, Vaxei and idke have very different styles.) "The rivalry comes in the form of battling in the ranking for the number one spot," Vaxei says.

The community, of course, likes to play up the rivalry between its top players. WholeWheatPete jokingly compared it to a zoo, which I got to experience as soon as I tweeted at idke to ask for his email for this story. Within minutes, the community noticed and started retweeting it. Eventually we landed at around 170 retweets for this innocuous ask. The response was mixed: Some people were just purely excited that an osu! player would potentially be interviewed. Some warned me not to be scared away by the "weird" community. Others wanted me to ask Vaxei instead. (Idke has been banned on Twitch in the past for "hateful conduct," according to a screenshot of a Twitch notification posted to Reddit . The notice said that idke "spammed racial slurs in chat while avoiding word filters.")

Rivalries are rife in osu!, but sometimes they're more with yourself than others. Getting to the top of the leaderboard is, however, certainly a driver for many of the game's top players. They're trying to beat their own scores, improving themselves as a way to move up the ladder. Both idke and Vaxei say they'll keep trying to improve, too, chasing a new record. Now that they've each broken the 1,000pp barrier, there's no telling how high they'll go.