FF7: New Threat. Complete pain in the ass to set up, but worth it. If you love the original FF7 it fixes and adds sooooooo much.
I never played it but the Thomas the Train mod for skyrim is hilarious.
Tale of Two Wastelands for Fallout 3 and New Vegas.
Gregtech: New Horizons
Technically a modpack rather than a mod though. I love grinding through technological advancements.
GB Mario 2 in full color
promods for ETS 2 and ATS 2
Mekanism, hands down.
Followed VERY closely by Fallout 2 Restoration Project.
I can’t believe I blanked on them in my own reply, but to piggyback off your Restoration Project nomination: the Talking Heads Addon and Talking Heads Actually Talk Mod for Fallout 2 Restoration Project (updated) are both absolutely insane, and breath some new life into the game while seamlessly slotting in next to the existing art and voice acting.
I love mekanism, often run it as my only mod
Sven-Coop for Half-Life 1.
I’ve played, almost daily, since the mod was released in January 1999. Over a quarter century. I’ve got admin in a number of servers, so a lot of days I’m just hopping on briefly to make sure the servers are running smoothly and no one is trolling. New maps are still being regularly released, many by people who have been mapping for it for a solid 15-20 years.
No idea of total hours. It wasn’t added to Steam until 2016, but I have multiple thousands of hours logged since then. I’ve got to be over 10-12k hours since the beginning. Easily.
Everything else in my life has shifted. Sven-Coop is my rock.
I couldn’t pick a single one, but I got endless joy from all the Quake mods back in the day. Not just level designs and sprite replacement, but complete weapon changes that made everything different, Quake Kart, Cujo, etc. It seemed the sky was the limit.
Rimworld multiplayer.
I really want to check that out, but it is incompatible with my favorite mod: Save Our Ship 2. I refuse to give up SOS2 just to play with another human.
Its pretty smooth but I’ve had a lot of desync issues because I have a long list of mods I try to play with.
They do PvP on the mod. Its pretty cool you have 4 teams and each player controls 1 pawn and the fight for objectives and capture and craft their way to victory.
The Fallout London mod for Fallout 4 was incredible. It’s like a an entire new game for free. They really captured the spirit of the Fallout universe. Better than anything Bethesda put out in the past couple years
I tried so hard to get this one to work and it just… didn’t. The intro played, vanilla FO4 started. I patched it again, vanilla intro started, crash to desktop. Even tried versions from Steam & GoG. Manually patched it, failed. Downloaded the patcher from GoG, failed.
That’s unfortunate. It’s a great mod (and the devs have done a bunch to fix crashes and load times).
Terraria - Calamity.
Expands the game to 2.5x the content.
Absolutely amazing, would recommend buying Terraria just to play it.
Garry’s Mod
It’s hard to think of any one mod that got remotely close to changing a game the way GMod did for HL2/CS:S/source engine titles. I spent thousands of hours in GMod as a kid, it added infinite teplaya ility to the HL2 campaign, forums like Facepunch and PHWOnline became my second home. There was a ton of content to be loaded from there and FPSBanana, the thriving webcomic scene was truly special.
I’m going to have to go with either the Create mod or Apotheosis, both for Minecraft. Both of them feel like they could just be part of the vanilla game, and at this point it feels wrong and weird for me to play the game without them installed.
I wanted to mention Create too.
I genuinely consider both mods to be more faithful the the vanilla experience than some the actual features added in more recent updates.
There are so many… I’ll just go with a couple
Fallout 3 Wanderers Edition always comes to mind for making that game so much better to play and more stable than the base game. I wouldn’t replay FO3 any other way
Elden Ring Seamless Co-op is what ER co-op should have been to begin with. God it’s so good I put another couple hundred hours in to replay every inch of ER+DLC with a friend.
I had two seamless coop playthroughs with friends. While the first one was buggy since it had just released, it is hands down some of the most fun I had with them. I’m shocked Fromsoft didn’t hire the developer to integrate it for real.
On the other hand, you should also know that you can play seamless co-op with mods. Seamless co-op with convergence mod is absolutely fantastic.
The Elden Ring Seamless Co-op is probably the only way I would have been able to finish the game and the DLC. It allowed myself and 3 others (who probably wouldn’t be able to complete it either) to beat most if not all the bosses.
I’ll check out Fallout 3 Wanderers Edition.
