Build the genome. Spend the ATP. Survive the siege.
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Adenosine triphosphate (ATP) is the energy currency of every living cell on Earth. When your muscles move, when neurons fire, when DNA is copied — ATP pays the bill. In ATP Siege, every action your microbe takes costs real ATP, calculated from actual biochemistry.
Every gene in this game is a real gene — fliC builds a real flagellum, cas3 is a real CRISPR defense system, hlyA is a real toxin. ATP costs come from published biochemistry literature. You learn biology by playing, not by reading a textbook.
You guide a microbial colony through four stages: pick genes, survive viral attacks, unlock mitochondria via endosymbiosis, then use gene editing tools (transposons, plasmids, CRISPR) to create divergent sub-cultures. Fill in DNA knowledge cards to earn ATP bonuses — learning biology is literally how you win.
Start with a gene bundle — Swimmer, Scavenger, or Crawler. Each is based on real prokaryotic biology.
Each gene expresses a real protein. Proteins enable real functions — movement, defense, nutrient uptake, division.
Every action costs ATP. Run out and your colony starves. Real oxidative phosphorylation math governs your energy budget.
Pick up DNA. Survive viruses. Unlock mitochondria. Then use CRISPR, transposons, and plasmids to edit your genome directly.
Fill in DNA knowledge cards with real biology facts. Correct answers earn ATP bonuses. Complete a card for rare rewards.
Choose from a branching evolutionary tree. Pick CRISPR immunity or toxin production — not both. Real evolutionary tradeoffs with permanent consequences.
Cells swim in genuine bacterial run-and-tumble patterns. Speed scales with ATP. High-nutrient zones pull them inward via 8-direction chemotaxis.
Sustain 30+ cells at >70% ATP to unlock mitochondria — a one-time evolutionary leap accompanied by an engulfment animation. 1.5 billion years in seconds.
Cas3 gives 85% phage resistance at 5 ATP/defense. When it works, a blue flash confirms the cleavage. Fail and the phage may insert genes into your genome.
Pick up loose DNA from the environment and dead cells. Study it to earn ATP bonuses, then express or discard. Every gene comes with a real scientific fact.
Pond, thermal vent, gut, open ocean — each with unique nutrient profiles, O₂ levels, and gene pressures. katG protects from O₂ toxicity. blaTEM1 survives antibiotics.
Builds the helical filament of the bacterial flagellum. FliC monomers polymerize into a rotating propeller that drives swimming at up to 30 body-lengths per second — equivalent to a human sprinting at 200 km/h.
Source: NCBI Gene ID 945702 · UniProt P04949
ATP Siege is designed to make microbiology, genetics, and evolutionary biology visceral and memorable. Students don't read about horizontal gene transfer — they watch a plasmid jump between colonies and change the outcome of their game.