Performance Update: The Classic Client Now Holds a Steady 25* FPS

Stable 25* FPS for the Classic Client

Now available for Season 21 Part 2-3 and Season 22 Part 1-1

Anyone who has run a MU Online server knows the scene. A castle siege begins, a boss spawns, an event fills the town, and the client starts to crawl. Players blame the server, server owners blame the players’ computers. The truth is simpler: the classic client was never built for what modern MU puts on screen. Dozens of characters in full sets, with wings, pets, muuns, guardians and giant mounts, all visible at once.

We decided to fix that properly.

What we have done

Over the past weeks our team rebuilt the most demanding parts of the classic client’s graphics engine. We did not patch around the problem or hide it. We took the routines that cost the most and made them do the same work in a fraction of the time.

The result: the classic client now holds its full 25 FPS, the frame rate the game was designed around, in situations where the original client used to collapse.

• Stable 25* FPS in everyday play. Towns, farming spots, events, party hunting: the game simply runs as it should.
• Crowds no longer kill performance. In our heaviest internal stress test, a large crowd of fully equipped characters with wings, pets and giant mounts, the original client dropped to single digits. Ours renders the same scene more than twice as fast.
• Smooth frame pacing. The original client delivered frames unevenly, which caused constant micro-stutter even when the FPS counter looked fine. Every frame now arrives exactly when it should, and you can feel the difference within seconds.
• Not a single visual compromise. No effects removed, no view distance cut, no lowered textures. Every optimized part produces exactly the same picture as the original, just much faster.
• Correct game speed. No frame-cap tricks that make animations, movement and skills run faster than intended.
• Zero setup. It works out of the box. Players do not need to change anything, and neither do server owners.

Players on older or weaker computers will notice the biggest difference. Those are the machines that suffered most until now.

About that asterisk

We prefer to be honest rather than print a number we cannot guarantee in every corner of the game.

25 FPS is the natural ceiling of the classic engine. In exceptionally busy moments, such as a massive siege with everyone stacked on a single screen and hundreds of effects firing at once, the frame rate may briefly dip down. Our lowest recorded FPS The difference from before is what happens next. Where the original client fell apart, ours dips for a moment and recovers.

Why this matters

There is no shortage of “FPS fixes” on the market. Most of them gain speed by taking something away: hidden effects, shortened view distance, or an unlocked frame cap that quietly breaks the game’s timing. That is the easy road, and players notice it.

We took the hard one. Every change was measured on real crowd scenes and checked against the original client, so the game looks and plays exactly as it should. This kind of work needs deep knowledge of the client’s internals, and that is what we do every day. It is also why our packages keep moving forward while others stand still.

Availability

The new performance improvements are available to all customers of our Season 21 Part 2-3 and Season 22 Part 1-1 packages as part of the latest client updates.

What’s next: 60+ FPS

25 FPS is the limit of the classic engine. Breaking through it without breaking the game is a different challenge entirely, and we have already taken it on. A 60+ FPS client is on its way and will be released soon. We will cover it in a separate article, so stay tuned.

Thank you for your continued trust.

The IGC-Network Team

_{* Stable 25 FPS in normal and busy conditions. In exceptionally crowded scenes the frame rate may briefly dip down.}