ProgressionParticle EnrichmentCostTurbo Motor, Fused Modular Frame, Cooling System, QuickwireUnlocksNitric AcidPackaged Nitric AcidNon-Fissile UraniumPlutonium PelletEncased Plutonium CellPlutonium Fuel RodParticle AcceleratorCopper PowderPressure Conversion CubeNuclear Pasta