Time Dilation

Time Dilation is the defining mechanic of EXODUS. In the game's fiction, every interstellar journey is sub-light, exploiting relativistic effects to cross light-years in subjective days or weeks. The cost is that everywhere the Traveler is not is moving forward in time normally. A trip away can mean hours for the player and years or centuries for the friends, family, and political map left behind.

How it works in fiction

EXODUS's starships move fast enough that, for the crew, only a small amount of time passes between systems. Outside the ship, time runs at its normal rate. The exact ratio depends on the trip, but a single mission can comfortably eat a decade of objective time. By the third or fourth Exodus, the cumulative drift between Jun and the home dynasty is measured in generations.

This is a deliberate use of the real-world relativistic effect, dressed up in genre conventions. The official tagline is that

• Each Exodus comes with a cost.

That cost is paid by everyone who stays behind on Lidon while the Traveler is gone.

How it shapes gameplay

Time Dilation is not a passive flavor mechanic. It is the engine of EXODUS's branching design and surfaces in concrete, in-game ways.

Companion bonds

Companions react to absence. A bond that was warm before launch can be cold after Jun returns: the companion may have aged, suffered, raised a family, lost one, joined another faction, or died and left a descendant in their place. Conversely, time apart can be the catalyst for a deeper bond, with NPCs revealing how much the Traveler's choices shaped their lives during the gap. The Companions and Crew article describes the cast affected by these jumps.

Faction politics

Factions on Lidon, on partner worlds, and in the wider cluster all advance during a mission. A government that was stable before launch may have collapsed by return. A trade deal Jun brokered before the trip may have outlived its parties. A rival Traveler Dynasty may have used Jun's absence to consolidate power. The game design exposes this through changed dialogue, repainted environments, and new questlines that did not exist before the Traveler left.

Technology and infrastructure

Equipment that was cutting-edge before a trip may be outdated on return. Common goods get cheaper. Specialized parts disappear from stock. Whole technologies move from "experimental" to "standard issue" while Jun was in transit, and others, sometimes the ones the dynasty depended on, fade out of memory.

Persistent narrative

Choices made before launch propagate forward. Promising a faction to return in a year and arriving in a century is not a meaningless line of dialogue: the in-game consequences track that broken promise. The game's lead writers describe the narrative as one in which every Exodus is a forced commit to long-term outcomes the player cannot personally see.

Why the mechanic exists

EXODUS is built on a hard-sci-fi premise: no faster-than-light travel, no instant communication, no comfortable cosmic shortcuts. The decision to honor that premise mechanically, rather than waving it away, is a design statement. It is what justifies the game's 40,000-year setting (the only way the original colonists could become the Celestials) and what gives weight to each side mission, each romance, and each faction contract.

Player-facing implications

The mechanic links directly to the rest of EXODUS's systems. The Combat and Gameplay article covers how a single mission plays out at the moment-to-moment level, while Worlds and Exploration covers how the visited worlds are structured to support repeat visits across decades.