Eidos is the elemental memory of existence; the essence of experience as retained and transmuted through consciousness. It is neither raw sensory data nor discursive knowledge, but an echo of the encounter itself: distilled, shaped by the mind and world in which it arose.

Within ATET, Eidos serves as the primary currency of understanding, transformation, and world-weaving.

Nature of Eidos

Each player experience, each Incarnation lived, each Thread spun, generates and accumulates Eidos. This process is not entirely under conscious control: players will find that certain experiences yield Eidos of unexpected kinds, or that the very act of seeking certain types of knowledge shapes what is remembered.

Eidos does not obey simple causal laws. Memory, imagination, trauma, collective myth, and direct encounter all contribute to its formation. Eidos is therefore the closest thing this universe offers to a metaphysical substrate; not energy or matter, but distilled meaning.

Philosophical Frame

In narrative and gameplay terms, Eidos embodies several overlapping ideas:

• From Daoism: the tension between unmediated experience (facts), narrative overlay (fictions), and constructed interpretation (faiths).
• From phenomenology: Eidos arises from lived experience, but is transformed by perception and reflection.
• From myth: Eidos is the story-stuff of the universe; the medium by which both personal destiny and cosmic patterns are recorded and replayed.

Gameplay Function

Progression

Players accumulate Eidos through each lived experience, embodied as an Incarnation, and traced as a Thread.

• Surviving or perishing in a harsh Tapestry
• Interacting meaningfully with its inhabitants and structures
• Witnessing or creating stories that echo beyond the Incarnation
• Forming or dismantling Faiths
• Uncovering or seeding persistent Fictions
• Directly observing or establishing new Facts

Accumulated Eidos unlocks new player abilities.

• The ability to craft or modify more complex Tapestries
• New options for crafting future Incarnations
• Narrative powers or tools that can alter the generation of new worlds
• Meta-progress across playthroughs

Narrative Economy

Eidos is not an explicit “XP bar” or points pool in the player UI, it is experienced diegetically through:

• The player’s access to new narrative branches or creation tools
• The recognition of the player’s accumulated “wisdom” by NPCs or the game world
• Subtle aesthetic or structural shifts in new Tapestries, reflecting the player’s learned patterns
• Lore fragments, visions, or omens that arise in proportion to accumulated Eidos

This ensures that Eidos is felt as memory and meaning first, and as currency second.

Typology (overview)

While a unified phenomenon, Eidos manifests in three interwoven modalities.

• Fact - the unvarnished memory of what is.
• Fiction - the narrative and imaginative frames that color experience.
• Faith - the deep beliefs and interpretive structures that shape identity.

Each of these has gameplay affordances and narrative consequences, to be detailed in their own sections.

Design Intent

Why this system exists:

• To express the game’s core philosophical theme: identity and world as narratives in tension with raw experience.
• To tie together progression, narrative emergence, and world-creation mechanics in an elegant loop.
• To give emotional and existential weight to player choices; Eidos carries the ghost of what you have done, and how you did it.
• To reward replay without reducing the game to mechanical optimization.

Key Design Notes

• Eidos should never feel like “points to grind.”
• The system must reward subtle and emergent play styles, not just overt heroism or power fantasy.
• The relationship between Fact/Fiction/Faith can be dynamic; e.g. a Fact can become a Fiction if misremembered or mythologized, a Fiction can crystallize into Faith, and Faiths can obscure or elevate Facts.
• Mechanically, the player should sometimes be surprised by what kind of Eidos a given experience yields, reflecting the unknowable alchemy of memory.
• Eidos should enable creative re-interpretation, not enforce correct play.