In 1993, Sandia National Laboratories released a report addressing a problem that wouldn’t matter for thousands of years: once you’ve built a lead-lined nuclear waste disposal bunker, how do you convince people in the far future not to dig it up? Since you can’t assume that these hypothetical people will speak your language or even have the necessary level of scientific development to know what radiation is, the problem is nontrivial. The report offered, among other things, a famous message to be inscribed on such a facility: “This is not a place of honor”.

The field of “nuclear semiotics” bloomed following the Sandia report: various thinkers suggested covering the site with menacing concrete spikes, establishing an “atomic priesthood” to guard the tomb, and designing architecture that made a “dissonant and mournful” whistle to dissuade explorers. French author Françoise Bastide and the Italian semiotician Paolo Fabbri proposed something especially novel: the genetic engineering of “ray cats”, whose fur would include a pigment that changed color or glowed when in the presence of ionizing radiation. By seeding the cultural idea that seeing a glowing cat meant invisible danger, one could, in theory, create a sort of biological Geiger counter paired with a taboo that would cause people to heed the warning.

Story Premise

Now, imagine that we did all of that at once. Then, advance the timeline 10,000 years.

Our protagonist is Yucca, an ambiguously gendered member of a humanoid feline species. These white-furred cat people live in villages dotting the post-post-apocalyptic desert, existing at a mostly pre-industrial technological level but with access to a handful of higher-tech devices due to salvaging remnants of the past civilization.

A few miles away is an underground vault beneath a landscape of black reinforced concrete spikes jutting out of the ground at irregular angles. The ( (unopened) entrance is a heavy locked hatch, fitted with a panel engraved with letters in an unknown language paired with simple pictures. Although the words are only partially deciphered, the picture in the center is widely interpreted as an  angel of death.

Everyone knows that anyone who goes down there is infected with something: your white fur turns blue, you sicken, and can pass that cerulean sickness on to others. They shun those with blue fur as curse-bearers according to wisdom passed down from millennia ago, but will nonetheless will trade for the resources buried within the vault in a thriving black market. The foolhardy and the desperate risk becoming sickly pariahs in hopes of salvaging a big enough score to retire in luxury. Yucca is no fool, but they are desperate: they have no home and no family, having drifted into town with a past they refuse to discuss.

Gameplay Loop

Although built to endure, the subterranean tomb complex began to weather and crack long ago. Although the main door of thick adamant remains impassable, the concrete walls can be breached if one digs deep enough to find the weak spots buried beneath the soil – is willing to expend some explosives cracking them open. Therefore, the basic minute-to-minute gameplay resembles the previous descriptions of Deep Time: a 2D side-scroller with procedurally generated, fully destructible terrain that you mine out for resources. Any ore or salvaged technology the player manages to retrieve can be taken back to town to sell, allowing them to buy equipment upgrades to make later delves easier.

However, the deeper you go, the higher dose of invisible corruption you’re exposed to. Thus, while Yucca begins the game with snowy white fur, each layer down they reach dyes it a further shade into the blue. NPCs will react differently depending on Yucca’s current shade: most people will shun you and increasingly refuse to deal with you, but those in the black market will treat you as more one of them and give you access to higher tiers of equipment upgrades. In addition, repeated loops into town unlock more dialogue with NPCs, letting you learn their stories and giving a greater understanding of what’s going on.

The vault is split into multiple sections storing different things: radioactive shamir, acidic alkahest, infectious protoplasm, and the like. Most of the challenge comes from figuring out how to even get near these things without injury, but you will also encounter active opponents: hostile creatures making their nests there, unscrupulous rival salvagers, robotic sentry units, and pitiable beings mutated by the depths.

Further down, even stranger unknowns lurk, unexposed to the light of day for thousands of years. A deep mystery will unravel itself by degrees as you read messages written by the builders, and discover the truth of the facility’s construction: the danger is still present, in your time, as it was in theirs.