Emulation is, of course, frowned upon, and when we want to play online with someone on the other side of the world, the Nintendo Switch might not be the answer.
We’ve always loved the clean simplicity and exciting combos of the original Super Smash Bros., but it’s difficult to find other people to play with in 2026. The same goes for anything that’s best played on outdated hardware. While many emulators have online multiplayer, games that require lightning-fast reactions generally work better in local multiplayer mode. However, that might be about to change, at least for the Nintendo 64.
On May 14, RMG-K, a variant of the RMG Nintendo 64 emulator, received an update that introduced rollback netcode to the entire emulator. However, developer CigNus noted that it is currently limited to two-player games. Input lag has been significantly reduced, and synchronization errors are much less frequent. Testers were able to play with only a 4-frame delay between Spain and Australia (previously, the delay was 9 frames).
Rollback netcode is a marvel of online multiplayer technology that makes fast-paced games playable even on weak connections. While latency-based netcode requires both players to catch up before button presses appear on the screen, rollback netcode predicts upcoming inputs and quickly corrects itself if necessary. The result is a level of responsiveness that simply cannot be achieved with latency-based gameplay.
As developer Heat shared on Twitter, the implementation of rollback in RMG-K uses the GekkoNet framework. The same framework is being used in a fan project that aims to natively port the PS2 version of Street Fighter III: 3rd Strike to PC. NyxTheShield, the programmer who worked on the rollback for RMG-K, tweeted that GekkoNet did most of the work and that adding the rollback was not that difficult.
It was honestly not that hard, maybe it wasn’t viable on the past but it took me an hour to profile save/load states from ram and see if the performance was good enough (it was) for rollback. Gekkonet did most of the lifting
– NyxTheShield (@NyxTheShield) May 16, 2026
Unnatended AI coding agent allucinating? No.
Codex as an automation/helper? yeah, like in every workspace in the planet currently.
– NyxTheShield (@NyxTheShield) May 2, 2026
It’s worth noting that the creator of the original RMG emulator appears to have criticized the RMG-K fork for its use of AI coding. RMG-K is offensive. They took the RMG code, wrote the modifications with Claude, and added a donation button to the project’s ReadMe, developer Rosalie241 wrote on Reddit. Having worked on RMG for years without LLM assistance, they found it disheartening and sad to see these vibe-coded forks pop up.
Developers involved in the project, such as NyxTheShield and CigNus, have mentioned using AI on social media. Nyx stated on Twitter that the rollback feature was implemented using Codex as an automation/assistance tool, as is done in every area of work.
Another goated project using my GekkoNet for netplay!
can’t wait to see where this goes. https://t.co/ytxjeFgs8q– Heat (@heat_xd) May 9, 2026
