: A modern, single-file compressed format that often combines the base game, updates, and DLC into one package. This is highly recommended for Cemu users.

The ethical dimension is the most nuanced. On one hand, downloading a ROM for a game that is out of print, unavailable on modern stores, and whose developers will never see a penny from a secondhand sale feels victimless. Many gamers argue that if the original publisher no longer offers a legitimate way to buy the product, the act of downloading it is not morally equivalent to shoplifting a new release. On the other hand, this "abandonware" argument holds no legal weight. The game is not abandoned; it is copyrighted until 70 years after the death of its creators. Furthermore, the availability of free ROMs can devalue the perception of software, harming the long-tail market for remasters and digital rereleases. The ethical gamer must weigh their desire for convenient, enhanced access against the principle that creators and publishers have the right to control how and when their work is distributed.

Unlike many older systems with a single standard file type, Wii U ROMs appear in several formats depending on how they were dumped:

: Cemu is the leading emulator for Wii U, offering features like resolution upscaling (up to 4K), graphic packs, and improved frame rates.

: Many enthusiasts use "homebrew" methods to run backups on original hardware. This often involves using tools like Wii U USB Helper to prepare files for an SD card.