By the way, I talked to Luke and Gary from Sigtrap in San Jose last year and they are cool with keeping this bug in and using it in speedruns, so it looks like no category split will be required.

I'm not entirely against creating a glitchless category if there is interest in it, but for now I will leave categories as they are.

For those interested in chatting on Discord, we piggyback off of the r/Descent Discord server at https://discord.gg/23qhrur - Feel free to join! We're mainly in #sublevel-zero-sr, but you can also find channels dedicated to other 6DoF games such as Descent, Overload, and more.

TFW there's new speedrun tech discovered less than a week before your marathon run. :)

I've let Sigtrap know about the bug.

My feeling is we should allow runs that include this bug. It's one of those fun speedrunning bugs that lets you squeeze out extra time and doesn't entirely break the game.

However if Sigtrap fixes it, I will just make a category for weapon glitches and throw all those runs there.

Well, vLKp just fixed it in 0.60.

I currently have no intention of fixing it in Retro, I've got enough to worry about over there.

Please provide some reproducible steps. I've tested this on 0.58.1 and Retro 1.4x6, and found the old method to not work.

Updated info on how to perform the exploit, as turns out I was reading retail 1.5 code, and the code changed in Rebirth 0.57.1.

I filed a bug with Rebirth: https://github.com/dxx-rebirth/dxx-rebirth/issues/366 If they fix it as I propose, the exploit would then revert to how it worked in retail 1.5.

While that works too, keep in mind the important thing here is that you saved the game after the boss teleported while the game time is high, preferably some hours in. You don't have to start a new game on the same level first.

Sirius just had me check Descent 2, and it looks like the bug is there as well.

OK, after some digging, I figured this out. Here is a technical explanation of what's going on by examining the boss movement AI. Note that both the level 7 and level 27 bosses have identical AI, just different weaponry and models.

Aside from normal movement and firing, it only has two other abilities: cloaking and teleporting.

In order to start a cloak, the boss must not already be cloaked. Plus, ONE of the following must be true:

1. The time between the game time and the time the boss finished cloaking must be greater than 10 seconds.
2. The boss got hit.

In order to teleport, ALL of the following must be true:

1. The boss is cloaked.
2. The time between the game time and the time the time the boss starts cloaking must be greater than 2 1/3 seconds.
3. The time between the time the boss finishes cloaking and the game time must be greater than 2 1/3 seconds.
4. The time between the game time and the last time the boss teleported must be greater than 8 seconds.

So there are a few variables here:

• The boss is cloaked or not

• The game time - This is the time since the game began. How is this set?

1. It is set to 0 upon starting a brand new game, regardless what level you start at.
2. It is set to whatever it was saved to upon loading a save file.

• The time the boss starts cloaking - How is this set?

1. It is set to 0 upon loading the .exe.
2. It is set to whatever it was saved to upon loading a save file.
3. It is set to the game time when the boss cloaks.

• The time the boss finishes cloaking - How is this set?

1. It is set to 0 upon loading the .exe.
2. It is set to whatever it was saved to upon loading a save file.
3. It is set to the game time plus 7 seconds when the boss cloaks.

• The last time the boss teleported - How is this set?

1. It is set to 0 upon loading the .exe.
2. It is set to whatever it was saved to upon loading a save file.
3. It is set to the game time when the boss teleports.
4. It is lowered by 2 seconds during a frame the boss is hit.
5. It is lowered by 4 seconds when the boss fires at you.

• How is this saved and loaded?

1. It is saved as the last time the boss is teleported minus the game time.
2. It is loaded as it was saved. Prior to 0.57.1, this was a bug. Now, since the game time is loaded as 0 from a save file, this is working as intended.

So now we know what the logic is, and can determine there are actually two bugs here. Both are related to the fact that several variables are NOT set to 0 upon starting a new game... only when opening the .exe.

The less important bug is with cloaking. After you've played a game when you've encountered a boss, your game time will need to pass the time the boss finished cloaking + 10 seconds... from your LAST game. OR it gets hit... so really this isn't that big a deal, because obviously you have to hit the boss to kill it. This just means it will never cloak UNTIL you hit it, so you can launch a barrage of missiles at it, and they will all lock.

The more important bug is with teleporting. After you've played a game when you've encountered a boss, your game time will need to pass the time the boss last teleported... from your LAST game. This is of course minus the 2 seconds per boss hit and 4 seconds per boss fire.

What this means for speedrunning:

Between retail 1.5 and Rebirth 0.57

• Start a new game in level 7 or 27, wait a couple hours, go aggro the boss and ensure it cloaks and teleports, then save that game.

Rebirth 0.57.1 and later, and all Retro versions

• Start a new game in level 7 or 27, wait a couple hours, go aggro the boss and ensure it cloaks and teleports. Then exit the game but don't close the EXE, and start a brand new game on level 1 and immediately save it.

Then:

• Before starting a speedrun, you should load that save file, and then IMMEDIATELY start a new game, and your bosses should NEVER teleport. As far as cloaking, the level 7 boss you can fire a bunch of homing missiles at him immediately because you know it won't be cloaked. The level 27 boss, however, will cloak occasionally because the level 7 boss would have cloaked, resetting that variable, which means homing projectiles won't be reliable.

There are significant enough changes that alter speedrunning (level generation, weapon rebalance, increased inventory, reactor changes) that warrant separating the legacy build and the live build.

The legacy build is still a thing, and I will continue to accept runs under that category. However, I highly recommend running under the new build.

I added a new option to select the gunship you used. It is a required field. I have backfilled all of the runs with the gunship used, so don't worry about doing that.

Happy flying!

I found that this does not like LiveSplit's SpeedRunsLive integration, and if you reload from saves it also resets the timer. Hmm, going to have to look into this more.

Also a note that this tracks the actual IGT as recorded by the game, in addition to RTA. Note that there's a "feature" in Descent where the IGT runs while you're in the exit tunnel, which you can hit escape to cancel, so IGT's still kind of bad.

I'm not yet sure how to get it to autosplit if you die in the mine. However, when I did a test run of the game, it split everything just fine from 1 to 27. Note it skips secret levels, counting them with the level you came from (so secret level 1 would be added to level 10's time).

Hey guys!

I'm working on an Autosplitter for games in the Descent series, and have Descent 1 working for Rebirth 0.58.1. Here is the link:

https://www.dropbox.com/s/ozfo8bm9wnf2ili/Descent%20Rebirth%200.58.1.asl?dl=0