Game objectives
- Emulator used: BizHawk-1.12.1
- Game version : v1.6
- BIOS : SCPH5501.BIN
- Heavy glitch abuse
- Aims for in-game time instead of real-time
About the game
The very first game of the action-adventure franchise, featuring Lara Croft as she sets out on an expedition to recover a mysterious artifact called the Scion.
Differences between PSX and PC versions
There are a few differences between the PSX and PC versions of the game, but nothing impactful on the route planning :
- Loading times on PSX between levels
- A 1 minute cutscene after the penultimate level that is only skippable on PSX
- Save points that are physical objects on PSX (on PC, you can save anywhere and anytime), so they can hinder or help Lara
Aims for in-game time instead of real-time
The game runs at 30 fps, so usually 1 in-game frame = 2 real time frame. On laggy places, the game may need more real time frame to advance to the next in-game frame (the worst I saw was 1 IG frame = 5 RT frame). Using IG time instead of RT made the route planning and the comparison with the RTA runs easier. For the rest of these comments, I will always speak about IG frames.
Speed and movement
| Movement | Speed (RAM) |
| Running | 47 |
| Standing jump forward | 50 |
| Rolling (first frames) | 50 |
| Swimming | 50 |
| Sliding on a slope | 50 |
| Running jump | 75 |
As you can see, the running jump is by far the fastest way to move, to the point where it is often better to take a seemingly non-optimal trajectory in order to make one more jump instead of running.
Now it is important to note that these are the speed in the RAM. In practice, the game rounds Lara's coordinates (X, Y, Z) because it only accepts integers. It means that depending if it rounds up or rounds down, Lara's true speed will be a little bit higher or smaller than the RAM speed. It also allows to adjusting either the X speed or Y speed while keeping the other one the same. The biggest example of this is that for a X speed of -75, the Y speed can be anything from 12 to -13.
When Lara is turning, her rotation speed increases by 45 each frame, until it caps to 1092 (on the ground) or 182 (in the air). However, when she is holding her guns (must be fully equipped) and turning on the spot, her rotation speed will reach 1092 almost instantly. While swimming, the rotation speed is always 1092 no matter what.
Route planning
Strictly speaking, there are only 3 enemies I need to kill to finish the game, one to trigger the end of a level (50 HP) and 2 to open locked doors (75 HP and 500 HP). Picking an item on the ground costs 73 frames (~2.43s) at the very least, so I needed to restricted the number of extra picks as much as possible.
| Weapon | Potential damage per clip | DPS | Potential frames saved over pistols |
| Pistols | ∞ | 6 | 0 |
| Shotgun | 48 | 21.82 | 174 |
| Magnums | 100 | 12 | 250 |
| Uzis | 100 | 15 | 300 |
So for the 3 enemies mentioned above, it is worth to pick any of these weapons/clips as long as it costs less time to pick them than their potential frames saved.
As for the medipacks, it is worth to pick them only if the alternative method to save enough health costs more time.
Glitches and tricks
- Corner bug : By entering into a corner with an angle close to 45°, Lara will get teleported to the top of this corner. There are a lot of methods to enter a corner, though I mainly used running jumps and rolls to do so.
- Wall bug : By hitting a wall while jumping, Lara is teleported to the top of this wall. It only works either if the floor under Lara is slightly-sloping or if she is between two floors of different height.
- Sidestep descending bug : If Lara does a sidestep while in the air (possible cases : start of a level, collapsible tiles, or if Lara is really close of a ledge), then she will be teleported to the floor below her without taking any damage.
- Dive bug : If Lara performs a dive and ends up at the edge of a ledge, she will not take damage even if the jump height would normally kill her.
- Delayed jump : By pressing the jump button at the right time, you can delay a running jump by one frame. While it isn't visible to the naked eye, it was useful from time to time.
Here is a table comparing my times with the best known individual levels time. Please keep in mind that in some cases I am at a disadvantage due to not having the same amount of weapons/medipacks or because I had to pick extra items for future levels.
| Level | TAS time | IL time | Time save |
| Caves | 1:16.50 | 1:16 | -0 |
| City ofVilcabamba | 2:40.93 | 2:44 | -4 |
| Lost Valley | 3:40.57 | 3:46 | -6 |
| Tomb of Qualopec | 0:56.23 | 0:50 | +6 |
| St. Francis' Folly | 4:21.67 | 4:44 | -23 |
| Colosseum | 3:40.80 | 4:40 | -60 |
| Palace Midas | 5:07.47 | 5:26 | -19 |
| The Cistern | 3:40.57 | 3:59 | -19 |
| Tomb of Tihocan | 5:59.90 | 6:37 | -38 |
| City of Kahmoon | 0:51.83 | 0:53 | -2 |
| Obelisk of Kahmoon | 2:14.63 | 2:24 | -10 |
| Sanctuary of the Scion | 5:42.13 | 6:37 | -55 |
| Natla's Mines | 3:40.10 | 3:57 | -17 |
| Atlantis | 1:55.73 | 1:56 | -1 |
| The Great Pyramid | 4:19.10 | 4:40 | -21 |
| Total (without hundredth) | 50:01 | 54:29 | -4:28 |
Now some comments about TAS specific stuff (aka RNG)
St. Francis' Folly
It took me a lot of time to figure out a way to manipulate the lions at the end, as they can easily delete my health bar in mere seconds.
Palace Midas
One of the save points was at a right place to allow me to continue my running jump without hitting the wall.
Sanctuary of the Scion
I used my rather useless magnums to kill two dangerous Atlantean on my way. It was unexpected that I managed to get away without using my small Medipack, but I made a good use of it in the last level.
Atlantis
As you can guess, this level was a RNG hell.
The Great Pyramid
The legless mutant has some invulnerability frames when he turns, so I moved so that he turned as little as possible.
Possible improvements or ideas
- A new method to get the two artifacts in the second level around 10~20s faster was found when I was already some levels further in the TAS. Redoing this level would pretty much mean redoing the whole TAS from the beginning, since I can't hex-edit any section involving RNG or lag (however, unlike 99% of PSX 3D games, some sections of the TAS can be hex-edited thanks to the cubic nature of the game), so I chose to continue the TAS without going back to level 2.
- Getting the Shotgun to kill Larson 8s earlier in level 4. However, while the Shotgun isn't too far out of my way, I also need to pick a shotgun clip in order to have enough ammo, and there is none on my way.
- Getting the secret Magnums in Colosseum to kill Pierre DuPont 170 frames (~5.67s) faster. Picking the Magnums here costs more than 170 frames, but if I also pick the large Medipacks (instead of the one in St. Francis' Folly), then it's possible that the total cost will be lower than 170 frames + the cost of the Medipack in St. Francis' Folly.
- Getting 6 clips of Uzis instead of 5. During the Legless Mutant invulnerability frames, there are some moments when one of the 2 bullets can hit him, but I can't waste any ammo since I have just enough to kill him. By having a 6th clip, I would be able to kill him some frames faster, but I don't think it is worth the time to get a 6th clip, even if I pick the double clips at the end of Atlantis instead of the one near the lever.
- Overall; I think my knowledge of the game improved along with the TAS, so I think most of the time to save over optimizations would be on the first levels.
Special Thanks
- The Tomb Runner discord for their advice and suggestions while I was making this TAS.
Suggest screenshot :
frame 37168 ("The only good Lara is a dead Lara" - Larson)
Fog: Excellent run! There was a lot of interesting glitches and strategies, as well as some entertaining moments throughout the run. Audience reception was also unanimously positive.
Accepting for Moons!
