Black Box is a Carta-powered standalone solo rpg (or minigame!) about hacking into a network you haven't intruded in before.
The PDF is 13 double pages, easy to read, and with a layout aesthetic that matches the game's subject.
The gameplay is a little like solitaire, in that you split your cards into a series of stacks and then try to whittle them down.
Black cards obstruct your progress. Red cards can be spent to remove them. Finding two jokers wins you the game.
There's a bit more complexity to it than that. You can roll to bypass black cards that you don't have the red cards to beat, but if you fail you take Heat. Heat serves as a timer before you're booted from the system, and as Heat accumulates each move becomes more costly.
Individual cards also have prompts, additional mechanics, plot twists, and assets that shape the game's narrative and tweak the mechanics.
At your discretion, there's a campaign mode where you can gain and spend money on one-shot items to help with troublesome hacks.
There's also advice on using Black Box as a minigame in another system.
Overall, Black Box feels like a neat solo card game about managing risk and trying to solve multifaceted problems. However, I think it also shines as a fully realized minigame that you can plug into another system.
With a little adjustment, you could even re-skin it as a dungeon room puzzle, or an espionage mission, or searching a library archive.
I recommend checking it out if you have the chance.
Minor Issues:
-Both password spray and brute force are used in the document, maybe interchangeably? Are these referring to the same mechanic?
-Core Gameplay and Password Spray describe the same mechanic differently. Core gameplay says you gain heat if you fail to roll the number. Password Spray says you gain heat if you roll the number.