• ProDuke Team Games now work as intended! — Team-based game modes (TDM, CTF, 1-Flag CTF, ATK/DEF CTF, TLMS) now launch with the correct game mode flags. The "Player Choices" UI now correctly enables the Team selector for these modes so players can choose their side, while disabling it in non-team modes.
• Color Selection restricted to Non-Team Modes — To prevent confusion and invalid arguments, the Color selection dropdown is now greyed out and disabled whenever a Team game mode is active. Color selection is exclusively available for DM, COOP, Survival, LMS, and Terminator modes.
• ProDuke Game Mode Auto-Presets — Selecting a game mode (DM, COOP, TDM, CTF, Survival, LMS, TLMS, or Terminator) now instantly wipes and applies the standard competitive default loadout for NetFlags, Weapon Flags, and Inventory Flags. You can still manually tweak them, which will automatically set the preset dropdown to "Custom".
• ProDuke Game Mode Command-Line Fixes — Fixed a critical bug where game modes with similar names were launching with the wrong /cN arguments. Team Dukematch (TDM) now correctly launches as /c3 (was falling back to /c1 DM), 1-Flag CTF and ATK/DEF CTF now launch as /c5//c6 (was /c4), and TLMS now launches as /c9 (was /c8).
• State Syncing Fixes — Switching between Team and Non-Team modes now instantly clears any previously selected (and now invalid) color or team from the server to prevent ghost badges from appearing in the player list.
• Lobby Server: Relay Port Leak Fixed — Fixed a backend bug where rejected room creations (like trying to host a second room, or using a duplicate room name) would permanently consume a relay UDP port. This prevents the relay port pool from slowly exhausting over time.

• Window Size Memory — The launcher now remembers your preferred window size. No more resizing the client every time you open it!
• Remember Last Nickname — Your last used nickname is now saved locally and auto-filled on startup. Just click "Connect".
• Live Usermap Refresh — If you add a new .map file to your Usermaps folder while inside a room, simply click the Usermap dropdown to instantly refresh the list without restarting.

• UDP Port Checker — The launcher now automatically tests if your UDP port 23513 is reachable from the internet when you enter a room.
• "Port Blocked" Badge — A red icon now appears next to players whose ports are blocked, warning everyone that Direct mode might fail for them. This icon syncs instantly for all players in the room.
• Anti-Flood Protection — Hardened the client-side UDP responders with rate limiting and exact packet-size checks to prevent the app from being used for network reflection attacks.
• Fixed Duplicate Rooms — Players can no longer create multiple rooms at the same time. The server will reject it, and the UI now disables the button to prevent double-clicks.
• NetDuke32 Nicknames — Fixed a bug where NetDuke32 players were stuck with their default config names. The launcher now correctly passes the -name command.
• NetDuke32 Relay Connections — Fixed a bug where NetDuke32 guests were trying to connect to the relay on the wrong port.
• NetDuke32 "Waiting for Players" Hang — Guests now wait exactly 10 seconds before launching. This guarantees the host has enough time to load the map and bind the UDP port before the guests try to connect.
• Port Checker Race Condition — Added a 500ms buffer before launching games to ensure the launcher has fully released port 23513 so the game can use it.

• ProDuke launch fixes — General fixes applied to the ProDuke launch commands for improved reliability and correct execution.

• ProDuke command-line fixes — the ProDuke command line is now generated correctly. Arguments are emitted in the order ProDuke expects, and the weapon and inventory flags use the correct /weapflags / /invflags syntax. Together these fixes resolve cases where ProDuke silently ignored loadout flags, which caused missing keycards and other starting-inventory issues in modes like Hotel Hell with the Classic preset.
• ProDuke connection fix — ProDuke's netlist.txt now uses interface 0.0.0.0 (IPv4) instead of the previous dual-stack [::] bind. The old bind caused a Windows WSAEFAULT error ("invalid pointer address") whenever ProDuke tried to send to an IPv4 peer, which broke connections to any room.
• Settings save fix — the ProDuke executable path in the Settings modal now saves correctly. Previously a typo in the save function meant the path was silently written as empty, which blocked joining or hosting ProDuke rooms with a "path not configured" warning. Users who hit this bug before updating should re-select their produke.exe and click Save one more time.
• Game Type dropdown fix — switching between different source ports (e.g. from NetDuke32 to ProDuke) a second time no longer fails to refresh the Game Type dropdown, which previously left options missing or incorrect.

• ProDuke source-port support — ProDuke joins NetDuke32, SDLDuke, and NBlood as a fully supported source port. All of its game modes are wired up: Dukematch, COOP, Team Dukematch, Capture the Flag, 1-Flag CTF, ATK/DEF CTF, Survival, LMS, TLMS, and Terminator. Read the ProDuke setup guide.
• NetFlags presets and custom flags — pick from the Classic, Alternative, Modern, or Hardcore NetFlags presets, or toggle every individual flag manually. Starting weapon and inventory loadouts are also configurable.
• Bots and match limits — enable ProDuke bots and set a count, plus optional score and time limits. When bots are disabled, /q0 is always passed so the game can't silently spawn default bots.
• Per-player team and colour sync — each player picks their own colour and team (when the game mode is team-based). Those choices sync to everyone in the room and are shown next to each player's name.
• Spectator and demo recording — per-player Spectate and Record Demo options, wired to ProDuke's -spec and /r flags.

• Nicknames must now be unique — if you try to connect with a nickname that's already in use by another player, you'll get a clear error message and be prompted to pick a different one. The client's nickname field re-enables and focuses so you can retype without restarting.
• Unidentified clients can no longer see the lobby — a client that fails the nickname check is now completely excluded from lobby broadcasts. Previously, a rejected client could still see the player list, room list, and lobby chat even though it hadn't successfully connected. It's now isolated until it picks a valid nickname.
• Re-identify without reconnecting — after a nickname is rejected, entering a new one and clicking Connect reuses the same WebSocket connection instead of opening a fresh one. Faster and cleaner.

• Player latency display — the lobby's Online Players list now shows each player's round-trip time to the lobby server, with colour-coded badges (green below 80 ms, amber 80–200 ms, red above 200 ms). Hovering a badge explains exactly what's being measured.
• Peer-to-peer latency inside rooms — once you join a room, each player's row shows the estimated latency between you and them. Numbers refresh every 10 seconds.
• Relay and direct modes both supported — relay rooms show ~Nms derived from the sum of two relay round-trips. Direct rooms show the real measured round-trip for the host, and ~Nms for other guests (via the host). The ~ prefix marks derived values; a number without a tilde is a direct measurement.
• Ping scope labels — pane headers now read Online Players · to lobby and Players in Room · via relay (or · direct) so it's always clear which kind of latency is being shown. Hovering either header gives a longer explanation.
• Relay and direct-mode probe support — the relay now echoes small NPS_PING_ UDP probes, and direct-mode hosts run a lightweight responder on port 23513 before the game launches so guests can measure their latency before clicking Ready. The responder releases the port automatically when the game starts.

• NetDuke32 relay now supports more than 2 players — previously the host proxy was capped at one guest slot due to NetDuke32's netcode instability over relay. With the patched NY00 build, NetDuke32 relay now scales to match NBlood and SDLDuke's multi-player support.
• NBlood rooms now default to "None" in the room list — the room-list Map column no longer shows a Duke episode/level placeholder for NBlood rooms. NBlood has no equivalent default map, so "None" is the correct initial value until the host picks a Cryptic Passage addon or custom map.
• Blood Addon dropdown is now always available — removed the previous restriction that disabled it when a custom usermap was selected. If both a custom map and Cryptic Passage are chosen, -ini CRYPTIC.INI still gets passed to every player.

• NBlood custom map transfer — hosts can pick a Blood .map file from a dedicated Blood usermaps folder, and every player downloads it automatically before launch. Once in-game, the map is selected from NBlood's own menu. Netplayseeker handles the file transfer; NBlood handles map selection. Duke and Blood map folders are kept separate in Settings so they never mix.
• Lobby peek — while inside a room, click the new Lobby button to switch back to the lobby and chat with everyone without leaving your match. A Back to Room button returns you to the room view. Your room stays open in the background.
• Version number is now visible in the client — the top bar shows the running version (e.g. v1.0.3) so you always know what you're on.

• NBlood multiplayer support — including the Cryptic Passage expansion via -ini CRYPTIC.INI.
• NBlood launch support — host uses -server N, guests use -client <ip>, both use -nosetup and -pname.
• SDLDuke fraglimit greyed out — SDLDuke does not support a frag limit, so the field is now permanently disabled for that port.
• NBlood skill lock — skill dropdown is locked to "No Monsters" for NBlood.
• Auto-updater UI — the client now checks for updates on launch and can install them in the background.

• SDLDuke and NetDuke32 multiplayer lobbies.
• Relay mode for guests behind NAT (no port-forward needed).
• Password-protected rooms with in-app password prompt.
• Lobby chat, room chat, and usermap sync for Duke ports.
• UPnP automatic port forwarding with relay fallback.

Linux troubleshooting

"error while loading shared libraries"
A required library is missing. Install the dependencies above, then check which one is missing:

ldd ./Netplayseeker | grep "not found"

"cannot open display"
You are running on a headless server or over plain SSH. A graphical session (X11 or Wayland) is required. On a server, use X11 forwarding (ssh -X) or run under a virtual display such as xvfb-run.

Nothing happens when double-clicking
The executable bit may not be set. Run chmod +x Netplayseeker from a terminal first.

WebKit rendering issues
Update your graphics stack:

sudo apt update && sudo apt upgrade

Relay Mode

Guests need zero configuration. The relay server accepts traffic from any NAT and forwards UDP packets between host and guests. Good for the majority of home networks. Supports up to 8 players for NBlood and SDLDuke, and up to 16 for NetDuke32 and ProDuke (when using the patched NetDuke32 build).

Direct Mode

Lowest latency — traffic flows host-to-guest directly. Requires the host to have UDP 23513 open on their router, either manually or via UPnP.

IPv6 Support

Netplayseeker only generates a netlist.txt for SDLDuke and ProDuke. ProDuke binds to [::] (dual-stack), while SDLDuke binds to 0.0.0.0 (IPv4-only). NetDuke32 does not use a netlist file (it connects via command-line IPs), so its IPv4/IPv6 binding is handled entirely by the engine itself—IPv6 is suspected to work for NetDuke32, but hasn't been fully tested. Peer-address discovery currently uses public-IPv4 services, so cross-internet sessions default to IPv4 until native IPv6 peer exchange lands in a future release.

VPN Notes

Commercial VPNs with symmetric NAT can break the relay for the VPN'd player. Real-internet play is unaffected. Workaround: only one side behind a VPN at a time.