A meme from the anime community, as it’s used millions of times in anime such as Demon Slayer
This meme is mainly synonymous particularly with the Attack on Titan fandom when in season 4 Eren Yeager repeats ‘tatakae’ in the mirror to motivate himself
Also known as simply, "Ouendan", Osu Tatakae Ouendan is a 2005 game originally made for Nintendo's 3DS, but later got reprogrammed by some random Australian guy named Dean "peppy" Herbert. It has a storyline, had some crappy animation, but was adapted in 2007 to a PC port, where you can click with a keyboard and move your mouse.