Gaming

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.

ARK: Survival Evolved. There are no corner pieces for sloped roofs without mods... I like a good sloped roof, and a building that's not just a square/a-frame.

@SevenSwell EU4's modding scene vastly improves the game, with a variety of total overhauls available. Same goes for most Paradox games actually - the modding scene is usually well taken care of.

But I'd be lying to myself if I said anything other then Skyrim AE.

I don't know if it counts as mods but I love playing Wind Waker randomizer :3

I have spent many happy hours playing GW2 and ESO. Mods have improved the GW2 experience significantly, but the game is still playable without them, if somewhat annoying. ESO is completely unplayable without lots and lots of mods, at least for me. I'm so directionally challenged that I gotta have my minimap.

I cannot speak for the entire S.T.A.L.K.E.R. series, but at least the first entry (Shadow of Chernobyl) is, while still very much playable, just so much better with a couple mods. And once you're familiar with the core gameplay, adding huge mods like Anomaly or G.A.M.M.A. (which itself is a modpack of Anomaly) adds many weeks worth of replayability to the game. Not even mentioning how good the game can look with these mods that touch it straight up into 2023. Of course, here and there you'll still notice that it's based on an older game, but it can easily compete with AAA releases of the past couple years in terms of atmosphere and immersion (especially the sound design).

OG Diablo II is still thriving and kept alive thanks to some amazing mods, such as Project Diablo 2. Improved graphics, wide-screen support, and tons of QoL changes and additional content every few months keeps the game fresh and arguably, better than all other official iterations of Diablo out there.

TES3MP was an amazing experience for Morrowind.

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!

Cataclysm: DDA comes with a shitton of mods bundled and is superfun

Arma 3. You could basically call the base game a platform for modding. DayZ as well as PUBG battlegrounds were originally mods for Arma.