The first thing I worked on asset-wise was our main character. She still doesn't have a name, but fortunately that's the easy part to change.

I'm working in Pro Motion NG - I've been a longtime Pro Motion user. PICO-8 carts export a 128x128 spritesheet image with the lower half being shared with tilemap data, although it's possible to do various compression tricks to expand that(probably out of scope here). This resolution limit immediately forced me to reconsider using the whole screen for a title, reducing the possibilities for composition to "girl and monster truck". I can scale them up, though, and maybe scroll the screen or something. Something to play with later.

The pixel art method I'm leaning on is the one castpixel is known for: solid lines and groupings of at least two same-color pixels, with little AA and basic shading. This technique gives a lot of emphasis to shape and proportion and speeds up the process of working on details: either they lock into place quickly and consistently, or you just can't fit them. The individual elements look a little bit blocky as a result, but are easy to parse.

The glasses got eliminated since they really dominated the facial design. I flirted with breaking the two-pixel rule to give her a side-smile, but eventually went for nose emphasis. The pose isn't super dynamic, but it's easier to compress with mirroring if need be.

Now, for the truck, I think I can do some kind of never-before-seen merger between "Tron" and "monster truck".

I ended up referencing a few different trucks, but primarily the pink-colored "Madusa". Then I reworked the sillhouette and details to reflect the more computer-y, Tron-like nature of the design. Monster trucks have a ton of exposed guts and they show more and more as an event progresses - trashing the body, overheating the engine, and popping the tires are all expected parts of the proceedings. That's a little bit hard to reproduce in a tiny resolution - I basically gave up and drew in some abstract lines. I gave it the name "AX", derived from the CPU register.

Now, for the in-game stuff, I had to figure out some terrain, vehicles, and our worms. I found my anxiety growing and growing as I worked on these assets, because it raised all kinds of questions about the details of the gameplay. First of all, to have a vehicle that can rotate, I would probably want to go with vector assets and therefore allocate some time to get a vector engine going(not really a huge issue - every game has its share of custom rendering code and I can copypaste some stuff I already have - but just one more thing to worry about). Second, I need to figure out what the levels are. I can't be bothered to do both procedural levels AND an interesting enemy AI under this time constraint, which means that I need a simple fixed map design. Leaning on the themes again, it looks like I have the options of "sectors" and "disks". So, a circular track, and I'm trying to clean up each sector of it. It makes sense for the circle to be made up of tiles, and to have some kind of system where I smash into the sectors to compress them and knock out the worms.

The worms themselves will probably be some kind of lightcycle-game AI. They're each trying to survive as long as they can, and when they hit "food" they reproduce, so they can take over the board quickly if you aren't fast. But they should leave behind a mixture of stuff that will make you crash and stuff that you can compress, e.g. an analogy like run-length encoding, where the uncompressible part is at the corners, so if you can make them run in straight lines that's actually better, you can shoot your compressor cannon and open up a gap, and you can optionally leave your own data trail if you want. That makes it a two-button game which is perfect for PICO-8. Most likely I should have the truck and enemies move four-directionally, but make it fine-grained and not locked to tiles like traditional Snake, so you can react quickly.

Now that I've written down this stuff I'm feeling a little more confident about resolving the gameplay again.