Gaming

minecraft for sure

I played vanilla Stardew Valley once, and now I'm on my second go around, and I've installed a bunch of qol mods so that I don't have to keep checking the wiki and my collections to see if I should keep or sell this item I got because I don't know if I need it for an achievement, and now I have a notification that it's an NPC's birthday and I can just check to see if I own or am carrying an item they have. It just makes the game less stressful for a completionist like me.

I love vanilla Terraria and Factorio but there are really fun mods out there that expand those games and don't let me play anything else!

Definitely Minecraft, you can turn it into a completely different game

Aside from the obvious minecraft... Arguably I'd say Factorio. They have a robust, feature-rich modding API built into the game that allows for relatively easy, wide ranging game play mods to be made very stable, and the number of mods has exploded as a result. The base game is amazing, but mods exist that quite literally triple the amount of game play and in some cases completely overhaul it into a totally new game. The support is amazing, and I wish more game companies could operate as efficiently as Wube does.

TES3MP was an amazing experience for Morrowind.

Minecraft is an obvious answer of course, but there are some other really good games out there that get made much better with mods. Some of my favourite examples of this would be Star Wars Battlefront II (2017) with the cool hero mods and bot mods, and then Ghost Recon Wildlands with the amazing First-Person mod.

Late to this post but to me it's Minecraft. It has such an insane amount of replayability and can be turned into a totally different game depending on the mods and whatnot.

I already answered differently, but I want to put out that the STALKER fandom is held together by mods. There are everything from almost invisible bug mods to an entire standalone mod. STALKER is one of those franchises where modding just seems like such a natural fit to round out the world and it’s amazing how the vast majority of mods intend to support the tone of the game rather than just adding in the whims of the mod maker.

Rimworld. The Vanilla Expanded mods alone have more content than the base game + all the DLCs

Skyrim

I don't know if improving is the right word, but the amount of transformative mods older games like Doom, Half-Life or Unreal Tournament (and not just shooters ofc) had, was wild.

Team Fortress started as a Quake mod, Counter-Strike as a HL mod, DotA as a Warcraft 3 mod.

Doom 1 and 2 would be a lot less interesting without mods, some of which change the game rather dramatically.

• Project Brutality turns it into a modern-ish shooter.
• Guncaster replaces the usual protagonist with a spell-casting, oversized-pistol-slinging dragon.
• DemonSteele replaces the protagonist with an anime character.
• My House and City of the Damned: Apocalypse turn it into a horror game.

Without mods, these games would have just been historical footnotes, not something a significant number of people still play.

Definitely RimWorld. There's so many mods that improve the base game. From QoL mods that make you wonder why that isn't default in the vanilla game, to mods that complety overhaul the actual win condition. Just overall a really fun, replayability, frustrating game.

Use mods though. It'll make it better. Check out p-music mod while you're at it.

Space Engineers the base game is great, but it comes to life with mods.

From simple things like a more immersive way to paint blocks or customised UI to to hole NPC Factions, new Weapons, dekorative Stuff, all the way to hole new physics systems like Water with flotation, Aerodynamics or re-entry heat.

I rarely play my games with mods, this game is one of the few exceptions. I even went so far as to create some very minor mods my self.

RimWorld. It's amazing what people can do from QOL to whole new factions or weapons. Amazing and the dev is very helpful during updates to try and not break mod support. Just blown away.

All of the older Grand Theft Auto titles were saved by modding originally (ignoring the remade definitive edition trilogy of course) GTA III, GTA Vice City, GTA San Andreas, and even GTA IV were all released for older hardware and much different technology at the time they were released, so there's some weirdness getting each of the games to run without issues or well on modern hardware and modern Windows. GTA IV specifically has a notoriously bad PC port that is at times hard to play without any mods or community made utilities.

All four games are substantially better with mods, from small things like restoring the original soundtracks for each of the games that have since been patched out due to licenses expiring, improving performance and stability, bug fixes, and even things like widescreen support. (Original GTA San Andreas specifically looks amazing with widescreen support and some other mods throw in)

My favorite mod currently is the GTA IV downgrader, found on GTAForums, it downgrades the version of your game, making it compatible with all of the most important utilities and mods made by the community.

Minecraft has a pretty solid vanilla experience but the depth of things you can do with mods is pretty insane. I’m playing a pack right now that basically turns it into a rogue like dungeon crawler.

Factorio all the way. Get bored of finishing the game, or crafting the perfect megabases? Prepare for mods that can take 1000s of hours to finish. Perfection.

As always, the factory must grow.

I know it's not as rich or developed as the Fallout or Skyrim franchise, but my fun little time waste Stardew Valley is greatly enhanced by mods.

The base game is incredibly fun and simple, but even the most basic mods enhance the "quality of life", making some of the more surface time eating elements easier. But then you have entire new world maps, NPC's, quests and full DLC-esque mods such as STV Expanded almost a must-have for long term players.

As an FYI, I'd highly recommend the game to even the most hardcore gaming aficionados. It's refreshingly amusing and low-key, so when Elden Ring has you ready to throw your controller at the TV, it's a nice mental break.

Plus the guy that created it learned how from scratch and coded the whole thing solo- the source, the sprites, even the music. And every upgrade and addition he's made over the years, easily 2-3 DLC's themselves, he's given away for free. Support indie devs!

Some I've modded besides what you said (Bethesda RPGs would be like, 8 games or something for me) would be Cities Skylines, Deus Ex, Factorio, Stardew Valley, Mount & Blade, Terraria, S.T.A.L.K.E.R.: Shadow of Chernobyl, Stellaris, Oxygen Not Included, Project Zomboid, Darkest Dungeon, Kenshi, Battletech.

CounterStrike started as an Half-Life mod

Fallout New Vegas for sure, although many of the issues were fixed by the devs over the lifespan of the game. Mods are pretty much vital to run that game properly, however. Many issues with the engine and many core bugs have been fixed by the community, and it's honestly something where once you play with them fixed, it's hard to go back