Nintendo is pushing the Switch as a console to compete for attention from hardcore gamers. In a new step to prove that they just announced that they're bringing a remastered version of Dark Souls to the popular console. This is also a change from Nintendo who hasn't been known for showing a lot of support for third party software.
Nintendo had a Mini Direct presentation today and ended it with a short trailer. This trailer showcases the Dark Souls remastered and its May 25 release. This was already fairly exciting news, but right after this Nintendo released a statement that it would also include not only improved framerate and resolution, but also the Artorias of the Abyss DLC.
Nintendo has been pushing the Switch as a change in the direction of the company. They're pushing for more consistent releases, more third party support, and even more games aimed at hardcore gamers. They're definitely stretching their creative legs, and so far it seems to have been really working out for Nintendo.
Dark Souls has become a fairly popular game since Dark Souls III and games being compared to the series. So it makes sense that Nintendo would want to get something from them onto their hottest system.