Cemu, for quite a while, was a relatively low-key Wii U emulator. Its efforts to run games like Super Mario 3D World and Nintendo Land were mixed at best, often struggling to achieve playable framerates on impressive PC builds. Yet the launch of The Legend of Zelda: Breath of the Wild seemingly gave it a fresh start, as the hugely popular Nintendo Switch launch title was also a hit on Wii U, opening it up to emulation.

In late March we reported on the surprisingly rapid progress the team behind Cemu was making with the game; it's also been drawing a lot of funds on Patreon for that work. As it stands that fund has just under 8000 backers and is bringing in a staggering $34,000 per month, and that money is evidently paying off.

YouTuber CryZENx, who we've covered in the past for their impressive fan-builds of Ocarina of Time using the Unreal Engine, is evidently a backer as they have access to the latest build of Cemu - 1.7.5. What it shows is just how far the emulator has come, running Breath of the Wild at 30fps in 4K (though the video below tops out at 1080p).

Two things to remember - CryZENx is using an absolute monster of a PC, with emulators often demanding hefty rigs for running games. The second point is that this remains a legally dubious area - Nintendo is outspoken against emulators yet has done little about the likes of Dolphin and now Cemu over the years. A number of Cemu users also claim that they've purchased legitimate copies of Breath of the Wild to 'support' the game before then trying to run it at a higher resolution on their PC. Others, of course, are vocal about the fact they will try to play an emulation without buying a legal copy.

Emulating Breath of the Wild in particular is also a touchy topic, in that it's both a game for a discontinued system - in the case of the Wii U - and also a major hit on a console new to the market. 

Wherever you stand on those debates, it's nevertheless surprising to see such rapid progress with this Wii U emulator - in the case of Breath of the Wild there are still apparently graphical glitches and problems, but it's clear just how far it's come.

As we've said in the past, enthusiast emulation like this is still niche when considered within the broad scale of mainstream gaming. Not only has Nintendo done little to truly shut projects like this down, but interested users still require powerful PCs and a degree of tech savvy to get playable results; as a result the threat to Nintendo commercial bottom line may be minimal. Nevertheless, projects like this will always be controversial.

As the weeks and months pass Cemu continues to make rapid strides; it'll be interesting to see whether it's allowed to continue doing so through the rest of the year.