Estrogen Mod

Estrogen Mod turns pharmaceutical chemistry into a full Factorio production chain. Start from wood, extract plant sterols, and follow the biosynthetic route to estradiol — then esterify it into four long-acting hormone esters, compound them into injectable dose kits, and feed the results back into your labs as a researchable science pack.

Built for Factorio 2.1 (Space Age optional). Esterification needs acyl chlorides and a pyridine base, saponification runs on potassium carbonate and methanol, and your methyl-ester byproducts crack back into reagents in a closed recycle loop.

Features

60+ recipes across the full steroid pipeline, from phytosterol extraction through microbial degradation and aromatization to estradiol.
Four estradiol esters, each with its own fatty acid backbone and full synthesis route:
Valerate (C5) — your first, short-acting ester.
Enanthate (C7) — the classic long-acting ester, built from castor/MCT oil oxidative cleavage.
Cypionate (C8) — ring-structured, intermediate duration.
Undecylate (C11) — ultra-long-acting, split straight from castor-oil pyrolysis.
Two pharmaceutical carriers — MCT Oil (clean and fast) and Castor Oil (traditional long-acting carrier with a bigger heal).
A researchable Hormone Science Pack, produced in chemical plants from your own vials and accepted by all labs.
An integrated research tree — every ester technology unlocks its production chain and its Hormone Science recipe.
An HRT buff system — doses heal and grant a configurable speed boost.
Character transformation system — transform your character to a female model after taking HRT doses (requires compatible character mod).
Dosing consistency system — maintain your transformation with regular dosing, with warnings and automatic reversion if you stop.
Permanent speed bonus — 10% speed increase while using the transformed character.
A dedicated "HRT Production" inventory tab with custom icons and a 7-technology research tree.
Two yield profiles — a forgiving default and an optional extra-harsh "realistic chemistry" mode.

Research Path

Basic Steroid Extraction (100, chemical science) — the estradiol precursor chain.
Organic Esters & Solvents (150) — oils, cleavage routes, pyridine, potash, methanol, isopropanol.
Pharmaceutical Packaging (350, after Advanced Material Processing 2 + Plastics) — vials, syringes, medical cloth, alcohol wipes.
Ester Valerate (200, chemical science) — the C5 chain, compounding, and Valerate Hormone Science — the entry point.
Ester Enanthate (500, chemical + hormone science) — the C7 chain, compounding, and Enanthate Hormone Science.
Ester Cypionate (1200, chemical + hormone science) — the C8 chain, compounding, and Cypionate Hormone Science.
Ester Undecylate (3000, chemical + hormone science) — the C11 chain, compounding, and Undecylate Hormone Science.
Hormone Optimization (infinite, after Ester Undecylate) — each level reduces cooldown by 5%, extends duration by 5%, and permanently increases running speed by 1%.

Esters are strictly gated: you can stockpile acids and reagents early, but no ester intermediate is craftable until its research unlocks. Only Ester Valerate can be researched without Hormone Science packs — every later ester consumes them, so the tree forces you through the full production line before it lets you advance.

Hormone Science Pack

Your compounded vials feed the labs. Each ester's research unlocks a Hormone Science recipe, and longer-acting esters yield exponentially more packs per vial: Valerate 1, Enanthate 2, Cypionate 4, Undecylate 8. Hormone Science is accepted by all labs and is required to research the enanthate, cypionate, and undecylate ester technologies.

Buff System

Dose kits inject on use: they heal and grant a temporary speed boost. The carrier sets the tradeoff, the ester sets the clock.

MCT Oil doses heal 100 and give the full speed boost.
Castor Oil doses heal 200 and give a half-strength boost for half the time.
Duration at full strength — Valerate 60s, Enanthate 120s, Cypionate 150s, Undecylate 300s.
Re-dosing is locked until the previous dose fades, so longer esters commit you for longer.

Character Transition

Transition your character after taking HRT doses:

Requires skins-factored + gear-girl
Transition unlocks after taking a configurable number of doses (default: 3).
Dosing consistency system — warning after configurable multiplier, reversion after higher multiplier.
10% permanent speed increase while using the transitioned character.

Mod Settings

HRT Buffs

Enable HRT Buffs (default On) — toggle the whole buff system.
Buff Strength (default 20) — the speed boost percentage, 0-100.
Cooldown Multiplier (default 1.5) — multiplier for dose cooldown duration.
Effect Length Multiplier (default 1.0) — multiplier for dose effect duration.

Character Transformation

Enable Character Transformation (default On) — toggle the transformation system.
Transformation Dose Threshold (default 3) — doses required to unlock transformation.
Consistency Warning Multiplier (default 17) — multiplier for warning timer.
Consistency Reversion Multiplier (default 20) — multiplier for reversion timer.
Force Girl Character (per-player, default Off) — auto-transform to female when unlocked.

General

- Realistic Crafting Ratios (default Off) — anchors yields to real-world chemistry, about 3.5x more raw materials per dose; requires a restart.

Requires Factorio 2.1 (Space Age optional, not required). Licensed under GPL-3.0.
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