SimCity 4 modders are cracking its deepest recesses in ever greater numbers, enabling extensive new changes

An alien spaceship hovering over a city in SimCity 4
(Image credit: Electronic Arts)

SimCity 4 modders are making previously-unheard-of DLL plugins and mods due to recent advances, enabling changes of tweaks to how it runs that prior modders would have considered impossible. Over the past few months these types of deep, game-altering mods, previously restricted to just a couple famous examples, have proliferated into dozens of tweaks to quality of life and brand new game features.

These new mods are so revolutionary because they access SimCity 4's DLL files, the library of binary files containing shared resources used across the entirety of SimCity 4. The biggest immediate impact is a mod enabling more building styles. That's huge: SimCity 4 players have had four tilesets of buildings for 20 years. Now they can have a lot more. There are also a host of mundane fixes marching out. Stuff like improving game stability, enabling new resolutions, adding autosaves, or more directly access information from under the game's hood about demand for building types.

The 21-year-old SimCity 4 Deluxe is considered by many to be the peak of city building games for simulating a rich, deep model of how cities operate. That preference for this specific game after all this time, and all the city builders that have come after, has fueled a rich modding and graphics development scene around the game for the past two decades. Modders were always hampered, however, because they didn't have access to the deeper reaches of how it worked: Just the fairly surface-level stuff.

The major announcement by a moderator on the longstanding Simtropolis forums brought attention to the new wave of mods, in part because the good news came with a caveat: The new wave of DLL mods would not work well if at all on older Windows disc versions, or macOS ports, of SimCity 4—just the current version available digitally.

The story's pretty straightforward: The first major DLL tweak was a cheeky little cheat file, SC4 Extra Cheats DLL, that Maxis developers had authorized the release of. The second was SC4Fix, a release by modder simmaster07 that solved two huge bugs in a modded SC4 game—but that mod was very specific and limited in scope. Since then, though, other modders have piled in on that work to expand on it and figure out how other things inside SC4 work, bringing the community to this watershed moment in modding.

"Thanks to the efforts of those continuing simmaster07’s line of work, namely Null 45 and memo, these sorts of revolutions are about to become more commonplace, bringing with them everything from improved game stability on modern systems, to long-requested new features and quality-of-life (QoL) improvements.  Null 45 has already released over a dozen DLL mods on the STEX since November, one of the most recent of which allows more Building Styles.  While I can’t reveal too much at this point in time, I will note that DLL files will become important components of major SC4 mods in the very near future.  Suffice to say, we’re entering a very exciting time in the SC4 modding community," said moderator Tarkus on Simtropolis.

Those interested in the SimCity 4 modding community can buy a copy of SimCity 4 Deluxe version 1.1.641 that's compatible with the mods via several modern sites, with most SimCity modders recommending the version purchased from GOG.

Contributor

Jon Bolding is a games writer and critic with an extensive background in strategy games. When he's not on his PC, he can be found playing every tabletop game under the sun.

Read more
Shadowheart's eyes go white as she holds a glowing magic artifact
Baldur's Gate 3 modder says the community's been making 'huge strides' towards custom campaigns: 'I think we'll see many of them refined, improved, and released this year'
The Sims 4 - a woman with red hair and a purple top exclaims with excitement
The best Sims 4 mods to expand your life sandbox
A citizen of a city
A lot is going on for Cities: Skylines' 10th anniversary—from freebies to new creator packs—but there's still a big ol' elephant in the room
Dark Messiah duel
Dark Messiah of Might and Magic gets co-op mode and extra content thanks to the mod community's collaboration with Ubisoft: 'To see it all come together has been very emotional for us'
XCOM 2 with Warhammer 40,000 customization and weapons modded in
When 2K removed its annoying launcher it broke a bunch of XCOM 2 mods
A citizen of a city
Cities: Skylines 2 celebrates 10 years of Cities with more nuanced homelessness and six new DLCs
Latest in Sim
Truckin' in the rain.
American Truck Simulator’s latest teaser is just a sound effect and no one seems to agree on what exactly it means
PowerWash Simulator 2 screenshots
'More evolution than revolution': PowerWash Simulator 2 is coming late 2025, and it's bringing online multiplayer and split-screen co-op with it
A child stands on top of a dinosaur exhibit, hugging the nose of a dinosaur skull.
As a real life museum employee, I'm a bit confused by the amount of pirate ghosts in Two Point Museum—but it's not going to stop me trying to make the most realistic exhibits I can
A citizen of a city
A lot is going on for Cities: Skylines' 10th anniversary—from freebies to new creator packs—but there's still a big ol' elephant in the room
Staring eyes in a face covered in oil
Death Stranding 2's PS5 release date is in June, let's hope it doesn't take 8 months to hit PC this time
Cities: Skylines 2 screenshot - street level at night
Cities: Skylines 2's asset editor remains a distant dream: Colossal Order is still working on it but says it's 'proven more technically challenging than initially anticipated'
Latest in News
A jester eating a banana
'He's just gonna show up one day and say, here's 100 new jokers:' Balatro's publisher doesn't know how big the 1.1 update will be or when it's coming
Gabe Newell in a Valve promotional video, on a yacht.
Marketing guy invents the concept of 'Real Steam' to explain why 'magic' games, AKA good games, end up selling: 'Don't tell Valve'
CHINA - 2025/02/11: In this photo illustration, a Roblox logo is seen displayed on the screen of a smartphone. (Photo Illustration by Sheldon Cooper/SOPA Images/LightRocket via Getty Images)
'Humans still surpass machines': Roblox has been using a machine learning voice chat moderation system for a year, but in some cases you just can't beat real people
Lucas Pope accepting the Pioneer Award at GDC 2025
Papers, Please creator Lucas Pope says 'it's a tragedy' his 2013 immigration sim now feels so on-the-nose: 'You want your work to be relevant, but at the same time, wow, I really wish it was not that f***ing relevant'
A stylized drawing of a horned demon with a skull for a face and glowing eyes peering over a forest cabin.
Bloober Team’s new horror label just unveiled an isometric survival horror game straight out of a comic book: ‘Avoid the Horned Man at all costs’
quake champions classic gordon freeman mod
Gordon Freeman joins a retro pandimensional deathmatch in crossover mod Quake Champions Classic