Reactor 4: NPP Builder is a small, sharp, indie-line reactor game from Arborea Games: not a grand strategy cathedral, not a grim simulator manual, and not especially interested in behaving like a responsible institution.

It lives closer to the shareware shelf: late DOS, Windows 3.11, chunky command-room panels, base-building pressure, and that old Apogee-era confidence that a dangerous idea becomes safer if the buttons are satisfying enough.

You are placed in charge of a growing nuclear facility with one simple mandate: produce more MW.

The details are handled by cheerful forest-friend comrades, management optimism, and a broad expertocracy of people who watched the Chernobyl docuseries and are now functionally RBMK nuclear scientists.
What can go wrong?

Quite a lot, usefully.

Build Fuel Rod Assemblies for power. Add Coolant Pumps, Cooling Towers, and Control Rod Clusters before the core gets ideas. Expand into Nuclear Waste Dumps and Containment Spires when the waste counter starts looking less like a number and more like a legal argument. Bring Turbine Halls online to turn heat into credits, because civilization has invoices.

Later, the facility unlocks more ambitious decisions: RBMK Control Rooms, Plutonium Extractors, Thorium Breeders, the Demon Core, and even Solar Panels, included for ethical contrast and comic scale.

Every structure helps. Every structure also tends to create a new problem.

Expect:
- Isometric nuclear base-building with quick sessions and escalating pressure
- A balance between Power Output, Credits, Core Stability, Heat, Waste, and Radiation
- Upgradeable reactor components with useful side effects and less useful side effects
- Waste management that begins as an accounting issue and matures into a personality flaw
- Meltdowns, alarms, suspiciously calm UI panels, and a dry sense of institutional humor
- A retro industrial style inspired by command-center strategy games and old PC shareware energy

Reactor 4 is intentionally lighter, asymmetric, and a little rough-edged in the good way. It is a fun product, not homework. Build a base, push the output, overtrust the cooling plan, and discover whether your facility is a triumph of applied science or just a very expensive lesson with animated warning lights.

The forest comrades believe in you.
You are now one of us.

That should help.