Eras - Heliomance/Uncharted-Horizons GitHub Wiki

_{Design document §2}

A civilisation enters an era when it holds the number of breakthroughs above from that era or later. Entering an era unlocks the policy branches tied to it, applies the era's own uniques (some reach the whole game, such as a spy for every major civilisation once anyone enters a given era), raises Faith purchase prices, and changes embarked units' defence, research agreements' cost and the AI's valuation of cities. The fork's costs, cost scaling and discovery pricing do not depend on it: they follow the era of the row, or the civilisation's development. Base Civ V enters an era with its first technology from it, which suits a dense chain of techs whose leading edge is never far ahead of the rest. Here a single breakthrough can arrive well ahead of its era — through a specialist, or luck — and under that rule a Mathematics specialist would enter the Early Modern to Atomic eras 0.8–1.1 eras early (up to 1.7), firing game-wide triggers early for everyone. The counts are about a tenth of each era's expected discoveries, so a thin era needs fewer: a balanced civilisation then enters within about 0.15 era of its development, the thin Classical era about a third of an era late. They were measured on the rate-model candidate in the discovery workshop, so they depend on the discovery model's pace and must be confirmed once that is chosen. The previous counts (8, 12, 15, 18, 20, 18, 15) dated from the first draft and left entry up to an era behind development.

Each era is a span of the Insight curve: a civilisation's development is in an era while its cumulative Insight lies inside the span. Up to the Early Modern era, an era's discovery price is its span ÷ its expected discoveries (§1.2), so each discovery costs the same share of the era, and the spans are set so that discoveries come at an even pace (v3.108). Two exceptions smooth the opening (v3.123). The Ancient era, whose many small breakthroughs had come faster than one a turn, is priced 1.5× its even-pace price, with its span to match. The Primitive span is 1.3× its expected discoveries' worth at its old price: civilisations are still finishing Primitive breakthroughs when its Insight runs out, and the longer span keeps development's entry to the Ancient era within 6–9 turns of their entry by the count above, as before, rather than 10–14. The last three eras follow base Civ V's own timing instead (v3.122, provisional): a good player's development enters the Atomic era around turn 228 and the Space era around turn 264, as base Civ V's does and about when civilisations enter them by the count above, and leaves the Space era around turn 320. Their prices are their v3.108 ones, the Space era's ×1.05 (v3.124), set by the design's hardest constraint: a science victory takes as long as base Civ V's for the same player on the same economy, within five turns either way, because domination, cultural and diplomatic victories are unchanged and balanced against base Civ V's game length. The reference is base Civ V's own tree, simulated to a launched spaceship on the same income: turn 305 on a good economy and 380 on an average one. (v3.122's dearer late prices, ×1.25 in the Modern and Atomic eras and ×2 in the Space era, made it 22–32 turns longer and were withdrawn in v3.123.) Base Civ V's own eras, its tech-column costs, are shown for comparison; the fork's no longer coincide with them.

Until v3.122 development entered the Space era around turn 285 on a good economy, 24–29 turns after civilisations entered it by count, so the FTL race was bought at the ahead-of-time premium and finished before development reached the Space era. Now the Space era's span covers the race, from about when civilisations reach the unified theory to about when a good player wins. Measured on the full design (v3.125: all 15 victory conditions, 2,700 games with rivals at the same prices, none unfinished), the expert wins at a median of turn 304, the novice 307 and the average player 381, against base Civ V's 305, 305 and 380; civilisations enter every era by count within 9 turns of their development reaching it. The cost is the late pace. A game holds about as many discoveries as turns whatever the prices, since players discover nearly everything that occurs to them and prices only set how long it takes; and the Modern to Space breakthroughs take 85% of the Insight spent on discoveries, so they cannot get dearer without lengthening the science victory. Fewer late breakthroughs are the lever: v3.124's merges, cuts and demotions, with Competing Solutions' lock-outs now measured, bring a good economy from about 1.26 discoveries a turn from the Modern era on, counting rivals' knowledge, to about 1.16 (v3.125), and an average one from about 1.0 to 0.93. The merges shortened the science victory, so the Space era's price rose ×1.05 to restore it.

Breakthroughs by era: Primitive (49) · Ancient (73) · Classical (43) · Medieval (41) · Early Modern (49) · Modern (76) · Atomic (84) · Space (122)