Pacing & Tension

What it is. Intensity over time is a curve, not a level you set once. A game that’s flat-out from minute one exhausts; one that’s flat-calm bores. The craft is peaks and valleys — escalating pressure punctuated by breather beats — so the session breathes, tension recovers, and the finale lands as the peak because you built up to it.

Player fantasy. “I can’t stop — but I can catch my breath.” The pull of rising stakes, the relief of a lull, the dread of the next climb. A shape you feel even when you can’t name it.

Why it works

Tension needs contrast to exist. A peak only reads as a peak against a valley; constant maximum is just noise the player tunes out. The breather makes the spike.
Breathers refill the flow tank. Sustained challenge without recovery slides the player from flow into anxiety and quitting (pattern-mastery-and-flow); the lull resets attention so the next peak lands.
The curve can emerge from loops. pattern-feedback-loops and pattern-risk-reward build peaks without hand-scripting — a snowball is a rising slope, a push-your-luck run is a self-authored spike. Design the loop, get the curve.
The valley is where the other systems breathe. Downtime isn’t dead time — it’s where the shop, the draft, the plan, and the story live. A game with no valleys has nowhere to put its pattern-risk-reward decisions; the breather is the choice beat.

Levers

Lever	Shapes the curve	Example
Escalation slope	How fast pressure rises	Wave HP/spawn ramp; enemy density over a level
Breather placement	Where the valleys sit	A runner wave; a safe room; a shop between fights
Peak spacing	Rhythm of spikes	Mini-boss every N rooms; a crescendo mid-level
Finale weight	The last peak is the peak	Gate on “finale is the max”, not monotonicity
Session length	The whole arc’s footprint	Run vs level vs campaign (`system-session-structure`)
Downtime texture	What a valley does	Loot, dialogue, planning, catching your breath (`pattern-risk-reward`)

Applied across genres

Genre	The curve	The breather
Tower defense (`genre-tower-defense`)	Wave intensity climbs to a finale peak	Runner waves are the pressure break (FUN.md §8)
Horde survival (`genre-horde-survival`)	Superlinear spawn ramp	The level-up pick pauses the tide (FUN.md §6)
Roguelite (`system-session-structure`, `anchor-hades`)	Room → room → elite → boss	The shop/reward room between fights
Bullet hell (`genre-bullet-hell`)	Pattern density escalates per phase	Phase transitions (with mercy clears) reset (FUN.md §7)
Deckbuilder (`genre-deckbuilder`)	Act → elite → boss	Rest sites; the map-choice planning beat
Survival horror (`genre-survival-horror`)	Dread accrues on a fuel budget	The lit safe pocket at a traversal’s midpoint (FUN.md §16)
Narrative (`genre-narrative-decisions`)	Stakes rise across the reign	A quiet, low-Δ choice between crises

Overdone when…

Monotone escalation. Every wave strictly harder than the last with no dip — the player never recovers and the finale reads as “just another wave, but slower to die”. Gate on shape (each wave ≥ ~55% of the previous, finale peaks), not monotonicity (FUN.md §8).
All-breather / no spine. Endless low-stakes downtime — the game never grips. Valleys serve peaks; they aren’t the point.
Whiplash pacing. Peaks and valleys with no ramp between — jarring, not rhythmic. Ease into and out of spikes.
The false finale. The biggest fight sits mid-session and the ending fizzles — the curve should build to its last peak.

Verify / feel-gate link

Pacing is one of the few aesthetic concerns FUN.md makes into a hard assertion, via the wave-curve gate:

Assert the shape, not monotonicity (FUN.md §8). Gate on “each wave ≥ 55% of the previous, finale peaks” — a breathing curve, with deliberate breather beats, not a straight climb. Both CLAWSTRIKE and Norman the Necromancer pace waves with explicit breathers (FUN.md §8).
Pressure curve checklist (FUN.md Part 3). “Wave/pressure curve breathes — deliberate breather beats; finale is the peak; assert the shape” is a before-you-author-content gate.
No unlock deserts (FUN.md §14). For incremental/economy arcs, the pacing failure is a desert — a stretch with no new thing; balance-sim the whole arc and assert no gap (genre-incremental).
Session-length fit (system-session-structure) — the curve must fit the intended session footprint; a 40-minute arc in a 5-minute run has no room to breathe.

Worked micro-example

“A tower-defense run that builds to a finale instead of grinding flat.” The naive curve is monotone — every wave a little harder — and the “finale” reads as just a slower-to-die version of wave 12. Shape it instead: (1) escalate the combat waves in a rising slope; (2) drop a runner wave every third slot as a pressure break — a valley that lets the player retool and breathe; (3) weight the finale as the true peak, well above the prior maximum. Now the run has a shape you can feel. Prove it with the wave-curve gate (FUN.md §8): assert each wave ≥ ~55% of the previous and the finale peaks — a breathing curve, not a straight climb, and not monotonicity.

Composes with

pattern-feedback-loops — loops build the peaks and the comebacks emergently; the curve falls out of the loop’s gain.
pattern-mastery-and-flow — pacing is flow over time; breathers keep the player on the ridge across a whole session.
pattern-risk-reward — push-your-luck is a self-authored tension spike; the player draws their own curve.
system-session-structure — the container (run/level/campaign) sets the arc’s length and where its peaks can sit.