Planned Release Date: November 2026

About This Game

ONE HAND OF MATERIALS, ONE CHAIN OF REACTIONS

Split water with electricity. Heat copper in the oxygen you just made. Dissolve the copper oxide in sulfuric acid, drop in iron... and watch the copper come back.

H₂O → O₂ → CuO → CuSO₄ → Cu. That's one hand.

Paper Reactions is a roguelike deckbuilder built on real chemistry. Every card is a substance: hydrogen, iron, hydrochloric acid, copper sulfate solution... Choose the right conditions (ignite, heat, catalyst, electrolysis), make something new, and feed the product into the next step.

HOW IT PLAYS

• Build reaction chains — run several reaction steps per hand. Products return to your materials, ready to react again or to score.
• Make phase combos — submit 1–5 final cards. Solids, liquids and gases form scoring combinations.
• Grow talismans — combustion, displacement, neutralization, relays... talismans grow with your play style and stack multipliers.
• Build your lab — between stages, buy packs, research, and enhance your cards in the shop.
• Survive the round finale — the last stage of each round bends the rules: no bonus for metals, gases score zero, only two submissions...

24 STAGES, ONE EXAM

The standard challenge is 8 rounds, 24 stages. At the end, your run is marked like an exam paper: red-pen underlines, a circled score, a stamped grade.

• Clear all 24 → A
• Double the final target → A+
• Fall short → graded B+ to D by how far you got

AFTER THE EXAM: ENDLESS

Clear the standard run and keep going. Endless Mode awards bronze, silver, gold and diamond medals, and each difficulty has its own Steam leaderboard, ranked by stages cleared, with ties going to the faster time. See a great run? Copy its seed and try to beat it.

FEATURES

• 360+ real, balanced chemical reactions and 130+ substances
• 50+ talismans and four themed starting decks
• Nine round-finale rules that rotate from run to run
• Three condition difficulties, from Simple (conditions hinted) to Complex (full condition list, phases hidden)
• Hand-drawn paper style with ink-line reaction effects
• Three manual save slots plus autosave; tutorial available any time
• Full controller support
• English and Simplified Chinese; single-player, fully offline

FOR CHEMISTRY FANS, AND FOR EVERYONE ELSE

No chemistry background needed. Simple difficulty hints the conditions, and the compendium is always one click away.

Know your chemistry? Every equation is balanced the way a school textbook writes it — and on Complex, the hints are gone.

AI Generated Content Disclosure

The developers describe how their game uses AI Generated Content like this:

Generative AI tools were used to assist in creating some visual assets, in-game text, and English localization. This content was generated during development and integrated into the game. The game does not generate AI content during gameplay.