Castle Intrigue
A multiplayer social deduction game built with Unreal Engine 5, combining hidden motives, environmental murder systems, spatial evidence, AI simulation, and server-authoritative gameplay.
Status
Period
Category
Castle Intrigue is a multiplayer social deduction and covert-action game set inside a stylised 3D castle. Designed for 4–8 players, the game combines hidden motives, environmental interactions, spatial reasoning, evidence collection, and social deduction.
Unlike conventional deduction games built around fixed opposing teams, most players may have a motive to kill the castle lord, but they are not necessarily allies. Each player has an independent identity, objective, access route, and set of opportunities. Players must decide whether to execute a murder plan, interfere with another player, collect evidence, construct a believable timeline, or avoid suspicion until the final vote.
Overview
Core Gameplay:
- Each match is divided into three timed phases
- Players move through connected castle rooms, collect limited resources, complete private tasks, interact with the castle lord, and observe the actions of others
- Multiple murder methods: poisoning food, coffee, or books; constructing environmental traps; sabotaging floors, doors, and electrical systems; creating delayed or indirect causes of death; performing a restricted direct attack
- Nine murder chains defined, six selected per match under balancing constraints
- Completing a chain requires the correct items, location, timing, motive, and access conditions
- Players without murderous intent can investigate, photograph evidence, remove traps, move resources, inspect guard records, disrupt suspicious activity, or unintentionally assist another player
Evidence and Deduction:
- The central mystery is reconstructing what actually happened, not simply identifying suspects
- Evidence includes photographs, visible environmental changes, missing resources, guard inspection records, locked-door activity, room transitions, sound cues, completed tasks, and time-of-death discrepancies
- The castle is designed as a readable spatial system with rooms, controlled entrances, servant passages, and circulation routes
- Players build and challenge timelines based on physical movement
- Final accusation may contain multiple players in event of tied vote
- Outcome distinguishes between clean accusation, successful accusation implicating innocents, and complete investigative failure
- Individual scoring accounts for killers, contributors, failed attempts, judges, hidden heirs, and ordinary players
Technical Design:
- Unreal Engine 5 with C++, server-authoritative architecture
- Specialised modules for match phases, role assignment, murder chains, inventory, evidence, voting, sound propagation, AI players, balance configuration, match snapshots, event logs, account progression, achievements, and tutorials
- Core gameplay values centralised in balance subsystem
- Each match records random seed, balance version, role distribution, available murder chains, door states, resource placement
- Matches reproducible and support controlled balance experiments
- Python reference implementation for rapid rule validation
- 52 automated gameplay test cases covering role assignment, movement, inventory limits, murder-chain constraints, sound propagation, phase transitions, voting, scoring, and alternative match outcomes
- Browser-based playable demo
Technology Stack:
- Unreal Engine 5
- C++
- Unreal Gameplay Framework
- Server-authoritative multiplayer architecture
- Python simulation and testing
- HTML, CSS, and JavaScript
- Automated Unreal and Python tests
- Data-driven balance configuration
Background
Detailed project background and motivation will be documented here.
Technical Architecture
System architecture, data flow, and technical decisions will be documented here.