Nintendo has issued a number of DMCA copyright takedown notices aimed at hindering a popular mod that adds online play to a PC-emulated version of Super Mario 64, letting up to 24 players run around the game's world together as a number of different characters.

ROM hacker Kaze Emanuar says Nintendo issued takedown requests for several videos of Super Mario 64 Online gameplay on his YouTube channel. Those videos featured download links and instructions for installing the ROM hack, which have also been removed along with the videos.

The main video announcing the mod's launch had received more than a million views since going up early last week (an archived copy of that video is still up on IGN). Emanuar told Kotaku that "tens of thousands" of people were playing the game as of yesterday.

Nintendo also issued a DMCA request against Emanuar's Patreon page, which funded the creation of a variety of Super Mario 64 hacks and was earning its creator nearly $700 a month, according to a cached version from earlier in the week. Emanuar told Polygon the Patreon was "kind of like a side job to me" and was "100 percent independent of [Super Mario Online]."

Archived copies of the Super Mario 64 Online mod are still archived and available through a number of unofficial portals. Nintendo's takedown has had seemingly no effect on the functioning of the mod itself, which uses IP address sharing to set up direct connections between player-hosted servers.

Nintendo previously used the DMCA to remove Mediafire-hosted links for Last Impact, a Super Mario 64 mod Emanuar launched about a year ago with new levels and powerups for the game. "This means I can no longer link to or upload this game anywhere," Emanuar writes on a YouTube video description for the mod, which is still up as of press time.

Nintendo has a long history of using the DMCA to crack down on fan games and mods that use its intellectual property, including a promising HD remake of Super Mario 64 that was being developed in 2015.

"Nintendo’s broad library of characters, products, and brands are enjoyed by people around the world, and we appreciate the passion of our fans," the company said in a statement. "But just as Nintendo respects the intellectual property rights of others, we must also protect our own characters, trademarks and other content."