Overview and Design Pillars

Overview and Design Pillars

Note

Design stage. This page describes planned mechanics from the design document. Not implemented yet — see Roadmap (milestone M0 is in progress; gameplay starts at M1–M2).

Prompt Critical (working alternative title "Create: SCRAM") is a Minecraft NeoForge mod about an industrial complex "from coal mine to closed nuclear fuel cycle". It treats power generation, oil and gas, metallurgy and chemistry as engineering disciplines rather than "a block that outputs RF".

The player climbs a ladder of industries (see Progression):

coal and steam → steel and electricity → oil and gas → chemistry → nuclear.

Each industry depends on the products of the previous ones and supplies the next. The top of the ladder is the full nuclear fuel cycle, from geological exploration to deep geological disposal, and a reactor whose physics is described by real equations: point kinetics with delayed neutrons, xenon and samarium poisoning, and thermal hydraulics with phase change.

The complex is run by plant instrumentation and control (I&C) that the player builds. It grows with the plant: relay cabinets → analog computers → PLCs programmed in IEC 61131-3 languages → DCS and SCADA on CC: Tweaked → plant level (MES/APC). Mechanical power comes from Create.

Inspirations

The mod does not copy other games and mods. It borrows specific ideas that match its pillars. Every borrowing is recorded as a design decision (R19–R30 in the GDD).

Source	What is borrowed	What is deliberately left out
GregTech: New Horizons	quest route, mixed ore veins, voltage classes, per-chunk pollution, maintenance panel	progression through recipe grind, space
HBM's Nuclear Tech	core cartogram (top-down core map), fluid identifiers on pipes	weapons, nuclear explosions
Immersive Engineering	visible wires with sag, by voltage class	—
Create: Crafts & Additions, TFMG	electric motor on a Create shaft, piston engines	FE as the main energy
PneumaticCraft	instrument air as a dependency of pneumatic actuators	pressure as a universal energy
OpenComputers	PLC CPU tiers	—
Mekanism	per-face input/output configuration	—
Tinkers' Construct	casting molten metal into molds	—
Nucleares, Workers & Resources: Soviet Republic, Captain of Industry, Oxygen Not Included, Satisfactory	control-room feel, Soviet industrial aesthetics, spare parts as logistics, temperature and gases as physics, grid automation	—
Nobody	—	magic, space, weapons, NPC workers (they dilute the focus)

Design pillars

#	Pillar	What it means in practice
P1	Physics instead of magic numbers	Every constant is either physical (with a cited source) or marked [BALANCE] with a justification and exposed in the config.
P2	Readability through instruments	You learn the state of a plant from gauges, sound and vibration, not from tooltips. Everything measurable is measured by sensors that have error and lag.
P3	Automation as gameplay	The mod gives you parts, not finished solutions: sensors, registers, PLC function blocks (PID, cascade, selectors — as in a real DCS), CC: Tweaked. You design the control scheme, interlocks, tuning and algorithms. There is no ready-made "station controller" (except a training one in TRAINING mode).
P4	Proportionate consequences	Mistakes lead to realistic consequences, bounded by server policy. All destruction goes through a DamageBudget.
P5	Performance is a functional requirement	Simulation budget ≤ 3 ms/tick (p95) for the reference complex. A design that exceeds the budget is a bug.
P6	Safety by design	Hardware protection works independently of Lua and PLCs: the reactor trip system (RPS), the safety instrumented system (sis_logic_solver) on any hazardous plant, relief valves. Control rods fall under gravity when drive power is lost; SIS valves go to their safe position on loss of power (fail-safe).
P7	Coupled industries	No production chain is closed on itself: every industry consumes products of others. Sulfur from the gas plant goes to uranium leaching, coke-oven pitch goes into reactor graphite, refinery diesel feeds the plant's emergency diesel generators, helium from natural gas fills fuel rods. A new chain without at least one input from and one output to another industry is not accepted into the design.

Platform

Component	Base version	Role
Minecraft	1.21.1	—
NeoForge	21.1.x	mod loader
Java	21	language
Create	6.0.x (NeoForge 1.21.1)	kinetics, stress, fluids, Ponder
CC: Tweaked	1.113+ (1.21.1)	Lua computers, peripherals, monitors

• Mod id: promptcritical
• Base Java package: dev.denfry.promptcritical
• Build modules: pc-sim (pure Java simulation, no Minecraft dependencies), pc-api, and pc-mod (the NeoForge binding). See Architecture.

Optional integrations

All optional integrations are wired through conditional recipes and ModList.isLoaded. None of them is a hard dependency.

Mod	Use
JEI / EMI	recipe viewing
Jade	overlay — only "everyday" data, never instrument readings (pillar P2)
Serene Seasons	seasons: heating load, cooling tower efficiency, river level. Without it, the season is derived from in-game days
Simple Voice Chat	plant public-address system: intercoms by role
Sound Physics Remastered	occlusion and reverb for the Acoustics system
Xaero's Minimap / World Map	waypoints from the geological_map
Distant Horizons	long-range visibility of cooling towers, flares and derricks

For compatibility with other mods (TFMG, Create Crafts & Additions, Mekanism and so on), cross-industry fluids and items carry common NeoForge c: tags, and optional conversion recipes use neoforge:mod_loaded conditions.

Units and conventions

Inside the simulation everything is SI only. Conversion to "operator" units happens only in the display layer (HMI). The CC: Tweaked peripheral API returns SI values and offers conversion helpers.

Quantity	Internal unit	Operator unit
Pressure	Pa	MPa (absolute); kgf/cm² optional
Temperature	K	°C
Energy / specific enthalpy	J / J·kg⁻¹	kJ/kg
Power	W	MW (thermal MW(t), electric/mechanical MW(e))
Mass flow	kg·s⁻¹	t/h, m³/h
Reactivity	dimensionless (Δk/k)	pcm (10⁻⁵), fractions of β_eff ($)
Reactor period	s	s
Neutron flux	cm⁻²·s⁻¹	% of nominal power
Activity	Bq	Bq, Ci
Dose rate	Sv·s⁻¹, Gy·s⁻¹	µSv/h, mSv/h, Sv/h
Surface contamination	Bq·m⁻²	Bq/cm², counts/(cm²·min)
Length	m (1 block = 1 m)	m, mm
Grid voltage / current	V / A	kV / A
Grid active / reactive power	W / var	MW / Mvar
Gas volume	normal m³ (0 °C, 101 325 Pa)	thousand Nm³, million Nm³/day
Formation permeability	m²	mD
Fuel quality	dimensionless	octane number (RON/MON), cetane number

Sign conventions: reactivity ρ = (k−1)/k, positive ρ means power rising. Mass flow ṁ > 0 follows the connection direction (from → to). All pressures are absolute.

Time domains

The simulation runs in three time domains with different step sizes.

Domain	What it covers	Step	Time acceleration
FAST	neutron kinetics, thermal hydraulics, pump/turbine/rod mechanics, containment pressure, water hammer	0.05 s (one Minecraft tick), internal substeps allowed	1× (real time)
SLOW	Xe/Sm, decay heat accumulation, burnup, isotope buildup, chemistry, spent fuel cooling, corrosion	1 s (every 20 ticks)	K_slow = 72 [BALANCE]: one Minecraft day (20 min) = one day of "physics"
STORAGE	multi-year spent fuel storage, decay of high-level waste in repositories	1 min of real time	storage.k_storage = 8766: one real hour = one physical year

A value computed in SLOW is used in FAST as a quasi-static parameter, interpolated between SLOW steps. Decay heat is accumulated in SLOW, but its power is applied in FAST every tick. Other time multipliers: nuclide.k_burn = 4 speeds up fuel burnup (deliberately breaking the heat/burnup energy balance for pacing). Hardcore servers can set nuclide.decay_heat_clock = REAL_TIME so that decay heat is not accelerated.

Performance budget

Performance is a pillar (P5), so the GDD sets hard numbers.

Parameter	Target
Whole mod, reference complex	≤ 3.0 ms/tick (p95)
Nuclear island (4 reactors, 400 fluid network elements, 20 players)	≤ 2.0 ms/tick (p95)
One reactor (kinetics + core thermal hydraulics)	≤ 0.15 ms/tick
Radiation field per player	≤ 0.05 ms/tick average (1 Hz update)
Instrument network traffic	≤ 2 KB/s per player in a typical control room
Allocations in the hot loop	0 (pools, primitive arrays, structure-of-arrays)

The reference complex is: 2 T2a (PWR-type) reactors, 1 refinery with 8 process units, 1 gas processing plant, an oil field with 30 wells, 1 steel site (blast furnace, converter, rolling mill), 1 coke battery, a power grid with 60 buses, 40 PLCs and 10 SIS logic solvers, 20 players.

Subsystem	Budget, ms/tick
Nuclear island (kinetics, core thermal hydraulics, trips)	1.00
Fluid networks: water, steam, hydrocarbons, gases	0.60
Power grid (load flow, frequency, protection relays)	0.15
Reservoirs and wells (mostly SLOW)	0.10
Refinery, gas plant, petrochemistry, chemical processing	0.30
Metallurgy, mines, coke ovens	0.10
PLCs, SIS, relays, analog blocks, fieldbuses	0.30
Radiation and acoustics	0.25
Reserve	0.20
Total	3.00

See also

• Progression — reactor tiers, industry eras and the automation ladder
• Reactor-Physics
• Nuclear-Fuel-Cycle
• Architecture
• Create-Integration
• CC-Tweaked-API
• Roadmap