Multiplayer

Multiplayer Hub

Main Menu → Multiplayer

┌──────────────────────────────────────────────────────────┐
│  MULTIPLAYER                                 [← Back]    │
│                                                          │
│  ┌──────────────────────────────────────────────────┐   │
│  │  ► Find Match          Ranked 1v1 / Team queue   │   │
│  │  ► Game Browser        Browse open games          │   │
│  │  ► Join Code           Enter IRON-XXXX code       │   │
│  │  ► Create Game         Host a lobby               │   │
│  │  ► Direct Connect      IP address (LAN/advanced)  │   │
│  └──────────────────────────────────────────────────┘   │
│                                                          │
│  ┌──────────────────────────────────────────────────┐   │
│  │  QUICK INFO                                       │   │
│  │  Players online: 847                              │   │
│  │  Games in progress: 132                           │   │
│  │  Your rank: Captain II (1623)                     │   │
│  │  Season 3: 42 days remaining                      │   │
│  └──────────────────────────────────────────────────┘   │
│                                                          │
│  Recent matches: [view all →]                            │
│  ┌────────────────────────────────────────────┐         │
│  │ vs. PlayerX (Win +24)  5 min ago  [Replay] │         │
│  │ vs. PlayerY (Loss -18) 1 hr ago   [Replay] │         │
│  └────────────────────────────────────────────┘         │
└──────────────────────────────────────────────────────────┘

Five Ways to Connect

Method	Flow	Best For
Find Match	Queue → Ready Check → Map Veto (ranked) → Loading → Game	Competitive/ranked play
Game Browser	Browse list → Click game → Join Lobby → Loading → Game	Finding community games
Join Code	Enter `IRON-XXXX` → Join Lobby → Loading → Game	Friends, Among Us-style casual
Create Game	Configure Lobby → Share code/wait for joins → Start	Hosting custom games
Direct Connect	Enter IP:port → Join Lobby → Loading → Game	LAN parties, power users

Additionally: QR Code scanning (mobile/tablet) and Deep Links (Discord/Steam invites) resolve to the Join Code path.

Network Experience Help

For a player-focused explanation of relay/sub-tick timing and practical optimization tips, see network-experience.md.

Game Browser

Multiplayer Hub → Game Browser

┌──────────────────────────────────────────────────────────────┐
│  GAME BROWSER                                    [← Back]    │
│                                                              │
│  🔎 Search...   Filters: [Map ▾] [Mod ▾] [Status ▾] [▾]    │
│                                                              │
│  ┌────────────────────────────────────────────────────────┐ │
│  │ ▸ Coastal Fortress 2v2        2/4 players   Waiting   │ │
│  │   Host: CommanderX ★★★        Vanilla RA    ping: 45  │ │
│  ├────────────────────────────────────────────────────────┤ │
│  │ ▸ Desert Arena FFA            3/6 players   Waiting   │ │
│  │   Host: TankRush99            IC Default    ping: 78  │ │
│  ├────────────────────────────────────────────────────────┤ │
│  │ ▸ Combined Arms 3v3           5/6 players   Waiting   │ │
│  │   Host: ModMaster ✓           CA v2.1       ping: 112 │ │
│  ├────────────────────────────────────────────────────────┤ │
│  │   (greyed) Tournament Match   2/2 players   Playing   │ │
│  │   Host: ProPlayer             IC Default    [Spec →]  │ │
│  └────────────────────────────────────────────────────────┘ │
│                                                              │
│  Sources: ✓ Official  ✓ CnCNet  ✓ Community  [Manage →]     │
│                                                              │
│  Showing 47 games from 3 tracking servers                    │
└──────────────────────────────────────────────────────────────┘

Click a game → Join Lobby (mod auto-download if needed, D030)
In-progress games show [Spectate →] if spectating is enabled
Trust indicators: ✓ Verified (bundled sources) vs. “Community” (user-added tracking servers)
Sources configurable in Settings — merge view across official + community + OpenRA + CnCNet tracking servers

Server/room listing metadata — each listing in the game browser will expose the following fields. Not all fields are shown as columns in the default table view — some are visible on hover, in an expanded detail panel, or as filter/sort criteria.

Category	Field	Notes
Identity	Server/Room Name	User-chosen name
	Host Player Name	With verified badge if cryptographically verified (D052)
	Dedicated / Listen Server	Dedicated = standalone server; Listen = hosted by a player’s client
	Description (free-text)	Optional short description set by host (max ~200 chars)
	MOTD (Message of the Day)	Optional longer message shown on join or in detail panel
	Server URL / Rules Page	Link to community rules, Discord, website
	Tags / Keywords	Free-form tags for flexible filtering (inspired by Valve A2S); e.g., `newbies`, `no-rush-20`, `tournament`, `clan-war`
Game state	Status	`Waiting` / `In-Game` / `Post-Game`
	Lobby Phase (detail)	More granular: `open` / `filling` / `ready` / `countdown` / `in-game` / `post-game`
	Playtime / Duration	How long the current game has been running (for in-progress games)
	Rejoinable	Whether a disconnected player can rejoin (important for lockstep)
	Replay Recording	Whether the match is being recorded as a `.icrep`
Players	Current Players / Max Players	e.g., “3/6”
	Team Format	Compact format: `1v1`, `2v2`, `3v3`, `FFA`, `2v2v2`, `Co-op`
	AI Count + Commanders	e.g., “2 AI: Col. Volkov (Hard), Cdr. Stavros (Normal)” — names and difficulties, not just count
	Spectator Count / Spectator Slots	Whether spectators are allowed and current count
	Open Slots	Remaining player capacity
	Average Player Rating	Average Glicko-2 rating of joined players (AoE2 pattern — lets skilled players find competitive matches)
	Player Competitive Ranks	Rank tiers of joined players shown in detail panel
Map	Map Name	Display name
	Map Preview / Thumbnail	Visual preview image
	Map Size	Dimensions or category (small/medium/large)
	Map Tileset / Theater	Temperate, Snow, Desert, etc. (C&C visual theme)
	Map Type	Skirmish / Scenario / Random-generated
	Map Source	Built-in / Workshop / Custom (so clients know where to auto-download)
	Map Player Capacity	The map’s designed max players (may differ from server max)
Game rules	Game Module	Red Alert, Tiberian Dawn, etc.
	Game Type / Mode	Casual, Competitive/Ranked, Co-op, Tournament, Custom
	Experience Preset	Which balance/AI/pathfinding preset is active (D033/D054)
	Victory Conditions	Destruction, capture, timed, scenario-specific
	Game Speed	Slow / Normal / Fast
	Starting Credits	Initial resource amount
	Fog of War Mode	Shroud / Explored / Revealed
	Crates	On / Off
	Superweapons	On / Off
	Tech Level	Starting tech level
	Viewable CVars (subset)	Host-selected subset of relevant configuration variables exposed to browser (from D064’s `server_config.toml`; not all ~200 parameters — only host-curated “most relevant” settings)
Mods & version	Engine Version	Exact IC build version
	Mod Name + Version	Active mods with version identifiers
	Mod Fingerprint / Content Hash	Integrity hash for map + mod content (Spring pattern — prevents join-then-desync)
	Mod Compatibility Indicator	Client-side computed: green (have everything) / yellow (auto-downloadable) / red (incompatible)
	Pure / Unmodded Flag	Single boolean: completely vanilla (Warzone pattern — instant competitive filter)
	Protocol Version	Client compatibility check (Luanti pattern: `proto_min`/`proto_max`)
Network	Ping / Latency	Round-trip time measured from client
	Relay Server Region	Geographic location of the relay (e.g., EU-West, US-East)
	Relay Operator	Which community operates the relay
	Connection Type	Relayed / Direct / LAN
Trust & access	Trust Label	`IC Certified` / `IC Casual` / `Cross-Engine Experimental` / `Foreign Engine` (D011)
	Public / Private	Open, password-protected, invite-only, or code-only
	Community Membership	Which community server(s) the game is listed on, with verified badges/icons/logos
	Community Tags	Official game, clan-specific, tournament bracket, etc.
	Custom Icons / Logos	Verified community branding; custom host icons (with abuse prevention — see D052)
	Minimum Rank Requirement	Entry barrier (Spring pattern — host can require minimum experience)
Communication	Voice Chat	Enabled / Disabled (D059)
	Language	Global (Mixed), English, Russian, etc. — self-declared by host
	AllChat Policy	Whether cross-team chat is enabled
Tournament	Tournament ID / Name	If part of an organized tournament
	Bracket Link	Link to tournament bracket
	Shoutcast / Stream URL	Link to a live stream of this game

Filters & sorting:

Filter by: game module (RA/TD), map name/size/type, mod (specific or “unmodded only”), game type (casual/competitive/co-op/tournament), player count, ping range, community, password-protected, voice enabled, language, trust label, has open slots, spectatable, compatible mods (green indicator), minimum/maximum average rating, tags (include/exclude)
Sort by: any column (room name, host, players, map, ping, rating, game type)
Auto-refresh on configurable interval

Client-side browser organization (persistent across sessions, stored in local SQLite per D034):

Feature	Description
Favorites	Bookmark servers/communities for quick access
History	Recently visited servers
Blacklist	Permanently hide servers (anti-abuse)
Friends’ Games	Show games where friends are playing (if friends list implemented)
LAN	Automatic local network discovery tab
Community Subscriptions	Show games only from subscribed communities
Quick Join	Auto-join best matching game based on saved preferences, ping, and rating

Ranked Matchmaking Flow

Multiplayer Hub → Find Match

┌──────────────────────────────────────────────────────────┐
│  FIND MATCH                                  [← Back]    │
│                                                          │
│  Queue: [Ranked 1v1 ▾]                                   │
│                                                          │
│  Your Rating: Captain II (1623 ± 48)                     │
│  Season 3: 42 days remaining                             │
│                                                          │
│  Map Pool:                                               │
│  ☑ Coastal Fortress  ☑ Glacier Bay  ☑ Desert Arena       │
│  ☑ Ore Fields        ☐ Tundra Pass  ☑ River War          │
│  (Veto up to 2 maps)                                     │
│                                                          │
│  Balance: IC Default (locked for ranked)                 │
│  Pathfinding: IC Default (locked for ranked)             │
│                                                          │
│                    [Find Match]                           │
│                                                          │
│  Estimated wait: ~30 seconds                             │
└──────────────────────────────────────────────────────────┘

Ranked flow:

Find Match → Searching... → Match Found → Ready Check (30s)
  ├─ Accept → Map Veto (ranked) → Loading → InGame
  └─ Decline → Back to queue (with escalating cooldown penalty)

Ready Check — Center-screen overlay. Accept/Decline. 30-second timer. Both players must accept. Decline or timeout = back to queue with cooldown.

Map Veto (ranked only) — Anonymous opponent (no names shown until game starts). Each player vetoes from the map pool. Remaining maps are randomly selected. 30-second timer.

Lobby

Game Browser → Join Game
  — or —
Multiplayer Hub → Create Game
  — or —
Join Code → Enter code
  — or —
Direct Connect → Enter IP

┌──────────────────────────────────────────────────────────────┐
│  GAME LOBBY     Trust: IC Certified    Code: IRON-7K3M       │
│                                                              │
│  ┌──────────────────┐  ┌──────────────────────────────────┐ │
│  │ MAP              │  │ PLAYERS                           │ │
│  │ [preview]        │  │                                   │ │
│  │                  │  │ 1. HostPlayer (Allied) [Ready ✓]  │ │
│  │ Coastal Fortress │  │ 2. You (Soviet) [Not Ready]       │ │
│  │ 2-4 players      │  │ 3. [Open Slot]                    │ │
│  │ [Change Map]     │  │ 4. [Add AI / Close]               │ │
│  └──────────────────┘  └──────────────────────────────────┘ │
│                                                              │
│  ┌──────────────────────────────────────────────────────┐   │
│  │ GAME SETTINGS (host controls)                         │   │
│  │ Balance: [IC Default ▾]  Speed: [Normal ▾]            │   │
│  │ Fog: [Shroud ▾]  Crates: [On ▾]  Starting $: [10k ▾] │   │
│  │ Mods: vanilla (fingerprint: a3f2...)                   │   │
│  │ Engine: Iron Curtain  Netcode: IC Relay (Certified)    │   │
│  └──────────────────────────────────────────────────────┘   │
│                                                              │
│  ┌──────────────────────────────────────────────────────┐   │
│  │ CHAT                                                  │   │
│  │ HostPlayer: gl hf                                     │   │
│  │ > _                                                   │   │
│  └──────────────────────────────────────────────────────┘   │
│                                                              │
│  [Ready]  [Leave]      Share: [Copy Code] [Copy Link]        │
│                                                              │
│  ⚠ Downloading: combined-arms-v2.1 (2.3 MB)... 67%         │
└──────────────────────────────────────────────────────────────┘

Key interactions:

Player slots — Click to change faction, color, team. Host can rearrange/kick.
Ready toggle — All players must be Ready before the host can start. Host clicks “Start Game” when all ready.
Mod fingerprint — If mismatched, a diff panel shows: “You’re missing mod X” / “Update mod Y” with [Auto-Download] buttons (D030/D062). Download progress bar in lobby.
Chat — Text chat within the lobby. Voice indicators if VoIP is active (D059).
Share — Copy join code (IRON-7K3M) or deep link for Discord/Steam.
Spectator slots — Visible if enabled. Join as spectator option.
Trust label — Lobby header and join dialog show trust/certification status (IC Certified, IC Casual, Cross-Engine Experimental, Foreign Engine) before Ready.

Additional lobby-visible metadata (shown in lobby header, detail panel, or game settings area):

Dedicated / Listen indicator — shows whether this is a dedicated server or a player-hosted listen server (with host account name)
MOTD (Message of the Day) — optional host-set message displayed on join (e.g., community rules, welcome text)
Description — optional free-text description visible in a detail panel
Voice chat status — enabled/disabled indicator with mic icon (D059)
Language — self-declared lobby language (Global/Mixed, English, Russian, etc.)
Victory conditions — destruction, capture, timed, scenario-specific
Superweapons — on/off toggle (classic C&C setting, visible alongside crates/fog)
Tech level — starting tech level
Experience preset name — which named preset is active (D033/D054), shown alongside balance/speed
Game type badge — casual, competitive, co-op, tournament (visible in lobby header alongside trust label)
Community branding — verified community icons/logos in lobby header if the game is hosted under a specific community (D052)
Relay region — geographic location of the relay server (e.g., EU-West)
Replay recording indicator — whether the match will be recorded

Lobby → Game transition: Host clicks “Start Game” → all clients enter Loading state → per-player progress bars → 3-second countdown → InGame.

Lobby Trust Labels & Cross-Engine Warnings (D011 / `07-CROSS-ENGINE`)

When browsing mixed-engine/community listings, the lobby/join flow must clearly label trust and anti-cheat posture. Shared browser visibility does not imply equal gameplay integrity or ranked eligibility.

┌──────────────────────────────────────────────────────────────────────┐
│  JOIN GAME?                                                          │
│  OpenRA Community Lobby — "Desert Arena 2v2"                         │
│                                                                      │
│  Engine: OpenRA                 Trust: Foreign Engine                │
│  Mode: Cross-Engine Experimental (Level 0 browser / no live join)   │
│  Anti-Cheat: External / community-specific                           │
│  Ranked / Certification: Not eligible in IC                          │
│                                                                      │
│  [View Details] [Browse Map/Mods] [Open With Compatible Client]      │
│  [Cancel]                                                            │
└──────────────────────────────────────────────────────────────────────┘

Label semantics (player-facing):

IC Certified — IC relay + certified match path; ranked-eligible when mode/rules permit
IC Casual — IC-hosted/casual path; IC rules apply but not a certified ranked session
Cross-Engine Experimental — compatibility feature; may include drift correction and reduced anti-cheat guarantees; unranked by default
Foreign Engine — external engine/community trust model; IC can browse/discover/analyze but does not claim IC anti-cheat guarantees

UX rules:

trust label is shown in browser cards, lobby header, and start/join confirmation
ranked/certified restrictions are explicit before Ready/Start
warnings describe capability differences without implying “unsafe” if simply non-IC-certified

Asymmetric Co-op Lobby Variant (D070 Commander & Field Ops / Player-Facing “Commander & SpecOps”)

For D070 Commander & Field Ops scenarios/templates, the lobby adds role slots and role readiness previews on top of the standard player-slot system.

┌──────────────────────────────────────────────────────────────────────┐
│  COMMANDER & SPECOPS LOBBY                             Code: OPS-4N2 │
│                                                                      │
│  ROLE SLOTS                                                          │
│  [Commander]  HostPlayer      [Ready ✓]   HUD: commander_hud         │
│  [SpecOps Lead] You           [Not Ready] HUD: field_ops_hud         │
│  [Observer]   [Open Slot]                                              │
│                                                                      │
│  MODE CONFIG                                                         │
│  Objective Lanes: Strategic + Field + Joint                          │
│  Field Progression: Match-Based Loadout (session only)               │
│  Portal Micro-Ops: Optional                                           │
│  Support Catalog: CAS / Recon / Reinforcements / Extraction          │
│                                                                      │
│  [Preview Commander HUD]  [Preview SpecOps HUD]  [Role Help]         │
│                                                                      │
│  [Ready] [Leave]                                                     │
└──────────────────────────────────────────────────────────────────────┘

Key additions (D070):

role slot assignment (Commander, Field Ops; CounterOps variants are proposal-only, not scheduled — see D070 post-v1 expansion notes)
role HUD preview / help before match start
role-specific readiness validation (required role slots filled before start)
quick link to D065 role onboarding / Controls Quick Reference
optional casual/custom drop-in policy for open FieldOps (SpecOps) role slots (scenario/host controlled)

Experimental Survival Lobby Variant (D070-adjacent `Last Commando Standing` / `SpecOps Survival`) — Proposal-Only, `M10+`, `P-Optional`

Deferral classification: This variant is proposal-only (not scheduled). It requires D070 baseline co-op to ship and be validated first. Promotion to planned work requires prototype playtest evidence and a separate scheduling decision. See D070 § “D070-Adjacent Mode Family” for validation criteria.

For the D070-adjacent experimental survival variant, the lobby emphasizes squad start, hazard profile, and round rules rather than commander/field role slots.

┌──────────────────────────────────────────────────────────────────────┐
│  LAST COMMANDO STANDING (EXPERIMENTAL)                 Code: LCS-9Q7 │
│                                                                      │
│  PLAYERS / TEAMS                                                     │
│  [Team 1] You + Open Slot      Squad Preset: SpecOps Duo            │
│  [Team 2] PlayerX + PlayerY    Squad Preset: Raider Team            │
│  [Team 3] [Open Slot]          Squad Preset: Random (Host Allowed)  │
│                                                                      │
│  ROUND RULES                                                         │
│  Victory: Last Team Standing                                         │
│  Hazard Profile: Chrono Distortion (Phase Timer: 3:00)              │
│  Neutral Objectives: Caches / Power Relays / Tech Uplinks           │
│  Elimination Policy: Spectate + Optional Redeploy Token             │
│  Progression: Match-Based Field Upgrades (session only)             │
│                                                                      │
│  [Preview Hazard Phases] [Objective Rewards] [Mode Help]            │
│                                                                      │
│  [Ready] [Leave]                                                     │
└──────────────────────────────────────────────────────────────────────┘

Key additions (D070-adjacent survival):

squad/team composition presets instead of base-role slot assignments
hazard contraction profile preview (radiation, artillery, chrono, etc.)
neutral objective/reward summary (what is worth contesting)
explicit elimination/redeploy policy before match start
prototype-first labeling in UI (Experimental) to set expectations

Commander Avatar / Assassination Lobby Variant (D070-adjacent, TA-style) — Proposal-Only, `M10+`, `P-Optional`

Deferral classification: This variant is proposal-only (not scheduled). It requires D070 baseline co-op validation and D038 template integration. Promotion to planned work requires prototype playtest evidence. See D070 § “D070-Adjacent Mode Family” for validation criteria.

For D070-adjacent commander-avatar scenarios (for example Assassination, Commander Presence, or hybrid presets), the lobby emphasizes commander survival rules, presence profile, and command-network map rules.

┌──────────────────────────────────────────────────────────────────────┐
│  ASSASSINATION (COMMANDER AVATAR)                     Code: CMD-7R4 │
│                                                                      │
│  PLAYERS / TEAMS                                                     │
│  [Team 1] HostPlayer     Commander Avatar: Allied Field Commander    │
│  [Team 2] You            Commander Avatar: Soviet Front Marshal      │
│                                                                      │
│  COMMANDER RULES                                                     │
│  Commander Mode: Assassination + Presence                            │
│  Defeat Policy: Downed Rescue Timer (01:30)                          │
│  Presence Profile: Forward Command (CAS/recon + local aura)          │
│  Command Network: Comm Towers + Radar Relays Enabled                 │
│                                                                      │
│  [Preview Commander Rules] [Counterplay Tips] [Mode Help]            │
│                                                                      │
│  [Ready] [Leave]                                                     │
└──────────────────────────────────────────────────────────────────────┘

Key additions (Commander Avatar / Assassination):

commander avatar identity/role preview (which unit matters)
explicit defeat policy (instant defeat vs downed rescue timer)
presence profile summary (what positioning changes)
command-network rules summary (which map objectives affect command power)
anti-snipe/counterplay hinting before match start

Loading Screen

Lobby → [All Ready] → Start Game → Loading

┌──────────────────────────────────────────────────────────┐
│                                                          │
│                    COASTAL FORTRESS                       │
│                                                          │
│               [campaign-themed artwork]                   │
│                                                          │
│  Loading map...                                          │
│  ████████████████░░░░░░░░░░  67%                        │
│                                                          │
│  Player 1: ████████████████████████ Ready                │
│  Player 2: ████████████████░░░░░░░░ 72%                 │
│                                                          │
│  TIP: Hold Ctrl and click to force-fire on the ground.   │
│                                                          │
└──────────────────────────────────────────────────────────┘

Per-player progress bars (multiplayer)
120-second timeout — player kicked if not loaded
Loading tips (from loading_tips.yaml, moddable)
Campaign-themed background for campaign missions
All players loaded → 3-second countdown → game starts

Keyboard shortcuts

Iron Curtain — Design Documentation