Roguelike

What it is. A run-based game of procedural dungeons and permadeath. Each seed generates a fresh, connected world; you descend, adapt to what you’re dealt, and die — then run again, wiser. Variance is the content: no two runs are the same, and every one is fair.

Player fantasy / why it’s fun. “I read this seed’s hand and played it well.” The pull is fair discovery — surprise that never feels cheated, mastery of a system rather than a memorised map, and the “one more run” that a fresh seed always promises.

Pillars

Fairness ≈ connectivity. Procgen that always connects — stairs and all loot reachable — is the floor. Prove it across ~50 seeds before tuning any number. An unreachable objective is the genre’s cardinal sin.
Turns that always replay. Deterministic, seeded, turn-based: input edge = one world step. Pure-data state makes runs reproducible and bots possible — the sim is its own proof engine.
Discovery, not memorisation. The challenge is reading this seed’s items, enemies, and layout — a systemic mastery that transfers across seeds, not a memorised route.

The loop stack

Scale	The beat
Moment	One turn: read the tactical situation → the move that reads it best → the world steps.
Encounter	A room/fight: positioning, resources, and item synergies vs an archetype mix.
Session	A run: descend floors, build from what drops, push your luck deeper, die or win.
Meta	Between runs — unlocks, new items in the pool, knowledge of the systems.

Essential systems

System	Why it’s load-bearing
`system-procgen-design`	The engine of the genre — seeds, connectivity, variance-as-content, controlled randomness.
`system-meta-progression`	The between-run pull; unlocks that add options, ideally, over raw power.
`system-session-structure`	Run length and shape; floor count, descent pacing, the win condition.
`system-enemy-archetypes`	The threat alphabet each room composes from — readable, beatable minds.
`system-save-and-checkpoint`	Respecting time under permadeath: save-and-quit, run history, retry friction.

Content & difficulty model

Content is the pool + the generator. Author items, enemies, and room templates; the generator combines them. Depth comes from interactions in the pool, not from more rooms.
Difficulty ramps by depth. Deeper floors mix nastier archetypes and tighter resources. The generator scales the mix, not a global HP multiplier.
Variance with guardrails. Seed the RNG; clamp the range so a run is never DOA (no floor with zero healing available). Prove winnability with full-knowledge bots — they show a line exists, which is the honest claim for procgen (not that a human will find it).
Meta adds options, not a floor of power. Guard against the run being decided at the menu; unlocks should widen the pool, not trivialise it. See system-meta-progression.

Signature-mechanic seeds

Roguelike but the dungeon is a language you edit (mechanic-swap) — Baba- style rule tiles you rearrange between floors; the systemic mastery becomes literal. Pairs anchor-baba-is-you.
Roguelike but every death leaves a corpse that persists (structure) — Nemesis-lite memory across runs; past selves become this run’s threats. Pairs system-emergent-systems.
Roguelike but you see the whole seed once, then it’s dark (constraint) — a memory/planning roguelike; the discovery is front-loaded.
Roguelike but turns cost light (theme + constraint) — a lantern descent; every step spends a finite glow, making exploration a resource.
Roguelike but two heroes on one seed, alternating turns (perspective) — co-op descent; connectivity must serve two paths.

Common pitfalls

Unreachable objectives. A seed where stairs or required loot are walled off is unshippable. Connectivity sweep, always, first.
Memorisation over mastery. If the “best” play is learning fixed seeds, the procgen is decorative. Variance must matter.
Meta decides the run. If a menu unlock makes runs trivial, discovery dies. Options over power.
Variance that punishes randomly. A seed with no healing or an unwinnable drop feels cheated. Clamp the generator’s worst case.

Anchors

anchor-nuclear-throne — the tight run-based mastery loop; steal its legible enemies and instant-restart momentum.
anchor-dead-cells — the roguelite structure of permanent unlocks over impermanent runs; steal its meta-progression shape.

Verify

Prove it in FUN.md §10 · Traditional roguelike: seeded reproducibility, a connectivity sweep, a full-knowledge bot wins 10/10 random seeds, and turn-log replay determinism.

Composes with

system-procgen-design — the connectivity-proven generator at the core.
system-meta-progression — the between-run hook that keeps runs coming.
system-enemy-archetypes — the threat alphabet each seed spells with.