SilentKrabs on 11/2/2025 at 21:28
My friends and I have been desperate for co-op games lately, then I remembered that Thief 2 has co-op. I'm happy to say that my friends took an interest and we tried some fan missions out. Going in, I knew that most of them probably wouldn't work, but we decided to experiment and see which ones did. As far as I know, there aren't any threads discussing this, so I figured that I could start one documenting how fan missions behave in multiplayer. If anybody else has any anecdotes or information about how Thief 2 multiplayer behaves, then I can edit this post to include them if I have the time.
General Observations
1. You can only die twice before you become invisible and lose the ability to interact with the environment. Essentially, you get two lives before permanent death. Reloading a save before someone dies resets this, so save-scumming is mandatory unless you want to start the whole mission over again.
2. Reloading a save causes the bubble meter to permanently appear on people's screens, except for the host.
Specific Missions (in Alphabetical Order):
Cardinals' Sins:
You can read the initial text briefing and get to the item shop. Once everyone is ready, however, the game crashes for everyone except the host.
Compulsory Egress:
This one appears to work flawlessly.
Eclipsed:
My friends and I only played this one for a few minutes. The opening cutscene played without issues and we were able to load in without crashing. Only the host could read texts, however. I'll update this if we ever play it again.
Ravensreach:
The switches that control the doors and platforms leading to the fire and earth wings of the castle didn't work, so we couldn't progress any farther. It worked flawlessly up to that point.
WungusDasPungus on 15/2/2025 at 19:53
Quote Posted by SilentKrabs
If anybody else has any anecdotes or information about how Thief 2 multiplayer behaves, then I can edit this post to include them if I have the time.
I made a (
https://youtu.be/aRiVJqx9cnQ) video on setting up T2MP multiple ways and depending on how you go about it can lead to some varied results. For example, there's a very common bug with the current state of T2MP where you can't connect more than 3 players without the server bugging out and kicking everyone, but even if you use the (
https://www.systemshock.org/index.php?topic=12190.0) fixed version of the exe, the game was never meant to handle that many players and can cause scripted events and triggers to freak out and not work, or just straight up break the networking in half. Missions like First City Bank & Trust are almost impossible to beat since a script in that ends up completely emptying your inventory, including the mission-critical key you need for the safety deposit box.
Quote Posted by SilentKrabs
General Observations
1. You can only die twice before you become invisible and lose the ability to interact with the environment. Essentially, you get two lives before permanent death. Reloading a save before someone dies resets this, so save-scumming is mandatory unless you want to start the whole mission over again.
2. Reloading a save causes the bubble meter to permanently appear on people's screens, except for the host.
Still haven't quite figured out what causes these to happen, since sometimes the game will react perfectly fine when a player dies, or sometimes they become completely unable to be revived. I'm not sure what the correlation is yet.
As far as FMs go, I can add:
(
https://www.thiefguild.com/fanmissions/41527/old-habits-and-dead-wives) Old Habits and Dead Wives
mostly works, depending on if your networking can hold up through the whole mission.
(
https://www.thiefguild.com/fanmissions/4111/the-inverted-manse) The Inverted Manse has a problem on one of the difficulties where a conversation that triggers a fireball on an invisible brush doesn't activate, forcing you to use one of your explosive tip arrows to make progress.
(
https://www.thiefguild.com/fanmissions/16759/feast-of-pilgrims) Feast of Pilgrims has only one option of getting back up to the rooftops if you fall to street level, since it was meant to be death for a solo player anyway.
and (
https://www.thiefguild.com/fanmissions/67224/a-shadow-on-the-water) A Shadow on the Water has a similar issue, where the instakill water just straight up doesn't kill you, nor allow you to swim, so you just drown.
These are all that I could think of off the top of my head, but we're still testing a bit. If I remember/find anything else, I'll post it here.
SilentKrabs on 21/2/2025 at 23:45
I watched that video when I was setting up the game with everyone. Thank you for making it; you helped us out a lot. Only three of us played, although we still used the patched .exe file that you included.
I've always maintained that computers are irrational, but Thief 2 is comical in how it randomly breaks. It's as if the .exe file is brain-damaged. One of my friends is getting his doctorate in computer science (with a specialization in networking) and he insists that basic peer-to-peer co-op should be one of the simplest things in the world to implement properly.
Does a way exist to make Thief 2 output crash reports? The next time that I play co-op, I could save and post those for anyone interested.
WungusDasPungus on 23/2/2025 at 05:51
Quote Posted by SilentKrabs
I've always maintained that computers are irrational, but Thief 2 is comical in how it randomly breaks. It's as if the .exe file is brain-damaged. One of my friends is getting his doctorate in computer science (with a specialization in networking) and he insists that basic peer-to-peer co-op should be one of the simplest things in the world to implement properly.
The code at the core of the game is still primarily for singleplayer, and if I'm remembering correctly, the multiplayer mod itself was just unfinished old original code that was sort of cobbled together into a vaguely working state with ND. However, I got the help of (
https://www.ttlg.com/forums/member.php?u=61303) vfig for the FCB&T bug mentioned, which lead to them discovering that it's most likely memory corruption over the network, mixed with sync issues with the host. Its kind of all over the place, and vfig would be better at explaining it than I would be.
Quote Posted by SilentKrabs
Does a way exist to make Thief 2 output crash reports? The next time that I play co-op, I could save and post those for anyone interested.
It does! It's
"crash.dmp" in your Thief folder.
baeuchlein on 23/2/2025 at 18:09
AFAIK, the crash dump is not really a human-readable report, but rather the contents of memory written to the hard disk. Thief2.log does report some things about the game, but I am not sure whether it is helpful in the majority of cases or not.
Peanuckle on 26/8/2025 at 05:35
I've recently gotten my brother to play a little bit of Thief, and while he doesn't care for single player games, multiplayer is good times for both of us. We've played a few maps and they seem to be stable, though some things just don't work. Something I didn't expect is that if one player picks up an item, only that player gets it. Seems reasonable, except there are many fanmissions where critical items, like lockpicks, are set for the player to pick up as an artistic choice. 'A Night in Rocksbourg' is one of these, and only one player could have picks, another had the sword, etc. Made gameplay too tricky to continue.
I know that 'Hotel Clair-de-Lune' works fine, we finished it without trouble. 'Death's Turbid Veil' does not, as we ran into a button that breaks in multiplayer and prevents progression. I presume that any FM with complicated triggers and reliance on player position would have problems. I'll keep posting which maps work for us as we play.
Insurrection by Jeremy Catlin mostly works. I'm starting to think that any sort of button pressing is broken, as multiple missions with that device have failed to trigger. But the mission can be completed.
skylerbaggins on 4/9/2025 at 03:13
It's interesting to read your experience! I've had similar issues with multiplayer items; especially with keys or things designed as part of the mission art. For us, "Ominous Bequest" was smooth, but when it came to the parts with multiple triggers involving doors, it was prone to bugs. I've found that having the "main player" hold all the important items from the start can help alleviate the issues, but of course, it doesn't always make sense with gameplay. Do you think future fan missions should have a "shared loot/item option" for co-op?
(
https://thatsnot-myneighbor.io/) That's Not My Neighbor
Peanuckle on 9/9/2025 at 03:13
It would be amazing if FMs could be created so that one player picking up an item meant that all players got it. MP is broken enough as is, so doubling weaponry and items isn't really an issue. I have no dromed experience though, so I can't guess how much of a burden it would be on FM makers to account for multiplayer mode. I'd rather see a handful of MP-oriented missions. CoSaS is written as though other thieves are performing jobs while you are, though in truth it's just map script. Imagine if a mission actually had parts where people had to coordinate across the map, pulling levers and timing locks, distracting guards etc. Would be awesome. But again, I don't know how practical that would be.
One of my favorite things is to set up ambushes: Guards chasing one player are somehow not 'alert' to the other player, so they are free to blackjack the guards as they chase you. We dealt with many people in this Looney-Tunes fashion. You can also trade off, getting the guard to chase the other player, and then the original player is able to blackjack the guard even though they are still alerted. Funny.
As an aside, the FMs "Ghost House" and "Ten Little Taffers" break in multiplayer, due to several triggers dependent on player positioning. Multiple players means triggers fail to fire, or fire incorrectly. Curiously, I have found that any square-type button does not work in multiplayer mode, across a number of FMs. The OMs work, oddly enough. I have no idea what might cause this.
