Based on the 3D action adventure game for PC and N64, Indiana Jones and the Infernal Machine for the Game Boy Color is a top-down, "2.5D" puzzle platformer. Perhaps surprisingly given the simplicity of the target platform, the game is quite content-filled featuring 14 large levels that are rather punishing for human players as they have to complete every single one in one attempt. For that reason, I decided to examine TAS perfection for completing the game as quickly as possible.
Game objectives
- Emulator used: BizHawk 2.7
- ROM SHA1 checksum: 6d568438aa3b9b67c55aded582cec136b15c46d7
- Number of rerecordings: 21007
- Objective: Finish the game in as low time as possible
- Abuse taking damage in order to maximize speed
The game has very simple mechanics - you can run, jump and use items on the environment. The game appears to be quite solidly programmed as I was unable to find any game-breaking glitches such as wall clipping, wrong warping, invincibility, etc. (perhaps someone in the future will have more luck). Thus, this run focuses on optimal routing and precise execution. The main sources of saving time are the following:
- Ladder sniping - Precise jumps from great heights that land onto ladders in order to skip climbing them down (very slow animation) and avoid fall damage.
- Landing frames skip - Landing on a platform in a window of 2 frames around the apex of the apex of the jumping animation skips the landing animation frames and lets Indy to immediately continue moving after landing. This trick is used all around the game to quickly ascend upwards and every instance of it saves 13 frames.
- Frame-perfect horizontal jump - By jumping at the very last possible frame, it is possible to jump across a gap that's two tiles wide while also landing on a platform that is one tile higher than the starting platform. However, this only applies to gaps in the horizontal direction (left->right or right->left). This sort of jump was clearly unintended by the developers and it some platforming sections to be simplified or skipped entirely.
- Blind moving - Sometimes when a cutscene ends, you regain control Indy before the camera returns back to him. In those situations, you can save time by moving despite not being able to see where.
- Minimal healing - Opening and navigating the game's inventory is very time consuming. Thus, great care was put into avoiding unnecessary damage so that healing items don't have to be used in order to finish the level. In the end, healing is used only twice during the run. In both cases, the medkit is used when the inventory is already open because a puzzle item needs to be used and the small time loss incurred is more than made up for by the time saved by using up the extra health bar (usually by skipping platforming sections by dropping straight down from great heights).
Canyonlands
Easily the biggest skip occurs right at the start of the run. Nearly the whole level is skipped by sniping a ladder in the second half of the canyon.
Babylon
A template for future levels, Babylon features precise block pushing and fearless jumps. Indy has perfect air control which allows jumps around corners. Pressure plates only need to be stepped on for a single frame in order to activate. Puzzle pieces in the top part of the library can be collected mid-air which skips a landing animation and allows a perfect setup for whipping across the gaps. A ladder snipe saves time going back down from the library. In the final room, the puzzle pieces are placed down in such a way to minimize inventory navigation time.
Russian Border
A corner jump after exiting the cave skips a couple of jumps. All ladders in the tower are sniped. A block pushing section is simplified down to a single pull using the frame-perfect jump.
Tian Shan River
A very difficult level. A lot of unintuitive counter-steering and single frame inputs were used in order to avoid the walls while maintaining as much speed as possible.
Shambala Sanctuary
More frame-perfect jumps in the treasury. The clock tower descent is skipped with a ladder snipe. The clock puzzle is one-cycled rather than two-cycled (as is common by human players). The clock tower ascent is simplified with a corner jump. Two more ladder snipes are performed on the way to obtain the flower seed.
Palawan Lagoon
A very simple level consisting mainly of swimming and backtracking. A major skip was found in one of the outdoor areas where a corner jump onto the scenery skips several ladders and a platforming section. Difficult health management as the sharks are nearly impossible to avoid.
Palawan Volcano
Very tight health management. One attack from a fire golem was avoided by triggering a cutscene right in the middle of it. Block pushing in the final room is almost entirely skipped using corner jumps and frame-perfect jumps.
Teotihuacan
In the statue room, the amount of activations of the small circle orb is minimized because its rotation animation takes the longest. A seemingly glaring omission is not using ladder sniping to backtrack through the green and blue chambers. It turned out that backtracking the intended way is slightly faster (by about 75 frames each). Oh well.
Olmec Valley
A corner jump is used to skip directly to the first block. The backtracking after collecting Azerim's Part is skipped with a corner jump.
V. I. Pudovkin
The intended escape cutscene at the start can be skipped by pressing right against the door. A healing item is used in the warehouse in order to survive fall damage as this is faster than using Azerim's Part to cross the gap again. AI manipulation is used on the deck in order to avoid fatal damage.
Meroe
A lot of health management on fall damage. The scorpion at the entrance to the pyramid is killed in order to avoid fatal poison damage later. The Azerim's Part activation tile on the other side of the deep pit is used without moving the block away.
Nub's Tomb
RNG manipulation has been done on the music puzzle. When backtracking after obtaining Nub's Part, the doorway was used from one floor higher than is intended. Perfect health management throughout the level.
Infernal Machine
The main machine complex is entered from the other side by falling down a cliff which skips a lot of backtracking. The second healing item of the run is used at the same time as returning one of the machine parts in order to get the extra health that allows to skip the laser eye at the end of the level. Turner is killed while completely off-screen.
Aetherium
The final level is almost entirely a cutscene. The four conduits are activated in such an order so that the exit portal appears right next to Indy.
slamo: Claiming for judging.
slamo: Cutting 7630 frames of blank input from the end of the movie.
slamo: Welcome to TASVideos, nice run you've got here. Nothing looks sloppy at all, you've done well to find the tricks that you have, and all the IL records have been beaten. Great work for your first TAS, accepting!
