Marsnut

For the curious at heart. A pocket-sized collection of science-inspired games.
Made for a quick break, a little discovery, and one more round.

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How to Play ATP Budget

Survive a two-minute fight. Six 20-second waves increase the pressure and change cellular ATP demand. A resistant foe arrives in the final wave.

  1. Move and dodge. Move the mouse inside the arena to guide the cell quickly. Hold the left mouse button to fire at the nearest foe. Keyboard: WASD or arrows move; hold Space to fire. On touch, drag in the arena and hold the Fire button.
  2. Attack. Each defense pulse costs 3 ATP and one defense charge. Biosynthesis allocation replenishes charges. Viral-shaped foes take one hit; bacterial-shaped foes take two; the resistant foe takes nine.
  3. Guard and dash. Hold E or Guard to reduce collision damage while guard charge remains. Membrane transport allocation replenishes it when not guarding. Shift or Dash spends 8 ATP for an escape and brief invulnerability; cooldown is 2.5 seconds.
  4. Budget energy. Adjust four ATP sliders. Transport supports guard recharge; biosynthesis supports reload; movement increases speed; repair adds recovery. Needs change each wave. Upkeep still consumes ATP, and firing or dashing spends from the reserve. Avoid overspending.
  5. Refuel. Collect gold drops for 18 fuel points. Two additional fuel doses cost 8 reserve ATP each and restore up to 35 fuel points. Higher output makes more ATP but burns fuel faster; low oxygen limits respiration.

Keyboard extras: P pauses, H opens help, M changes sound, F adds fuel, R selects normal output, T selects higher output. Keys 1–4 select an allocation slider; + / − adjusts it. Help and hidden tabs pause the battle. Resume after returning.

Biology and game mechanics. Cells use ATP for transport, biosynthesis, movement, and maintenance. Combat pulses, guard shields, enemy hit points, charge pools, controls, rates, and scores are visual game abstractions. Real cells do not shoot pulses or deploy energy shields. Glycolysis can provide ATP without oxygen; mitochondrial respiration depends on oxygen.

Further reading: ATP and energy coupling · Energy production in cells