Frequently Asked Questions (Updated: August '21)

Basic Troubleshooting

IMPORTANT: If the problem remains ask for help either on the forum or via IRC #0ad, the game is maintained by volunteers who do all sorts of tasks, be patient.

Issue possible Solution
Setup related
Crash when starting the game Do you have any antivirus software running? Try disabling it temporarily or add an exception for 0AD.
Crash when starting a match Try disable Post-processing in the game options, while leaving Prefer GLSL on.
Game does not render correctly/
Rainbow colors
See this forum thread Game does not render correctly (22/Feb/21).
No replay files are generated Do you have any antivirus software running? Try disabling it temporarily or add an exception for 0AD.
Errors are displayed (1) Try to disable all mods not compatible with the new version via the Mod Selection page.
(2) If you cannot access the Mod Selection page, you should locate your user.cfg file (see wiki/GameDataPaths) and either delete it or search for mod.enabledmods. Replace this line with mod.enabledmods = "mod public".
How do I increase the user interface? Add gui.scale = "1.2" to your user.cfg file (see wiki/GameDataPaths), you can increase this number if you like, this will likely become an option with A26.
Where do I find my replays, save files and configuration files (e.g user.cfg)? See wiki/GameDataPaths
Game is lagging Yes, this is a general problem with the game. It will lag on most machines it is actually CPU bound, not your GPU. Try to play on smaller maps & limit population.
The game will only run as fast as the slowest CPU allows in multiplayer games.

Wiki/GamePerformance summarizes the problems, that need to be solved, to improve performance.
Frame rate - CPU and GPU workload (1) Every frame that is calculated by the GPU is "prepared" by the CPU, one of them will limit your frame rate (FPS). When you select graphics effects, you create additional workloads for your GPU and CPU, causing your framerate to drop. Current PCs are mostly CPU limited in 0 A.D. because the game is not yet multi-threaded. That means they usually only use 1 core. Since graphics effects mostly affect the GPU, you can (on newer PCs) choose the higher graphics effects without sacrificing performance.
(2) Heating up the hardware leads to thermal throttling of the hardware. This effect is especially known for mobile PCs. If the hardware gets too hot, it throttles its performance until the hardware cools down again. Therefore, a limited but constant frame rate is usually better than a frame rate that fluctuates due to thermal throttling.
(3) VSync will also limit the framerate to the framerate of the monitor (I estimate 60 frames/Herz).
See forum thread - Recommended FPS Throttling? (16/Dec/20)
When hosting a game, the PC/laptop can barely cope with the required technical prerequisites, leading to game lag. A way to ease the load on the PC/laptop is:
(1) Host a game, but let the host PC/laptop be a spectator.
(2) When the match starts, turn all graphics settings on the PC/laptop to a minimum, then choose one of the player's perspective. The idea is that normal observer/overload perspective allows you to see every detail on the map, which increases load. If you switch to a player's perspective, the PC/laptop only needs rendering what that player can see. This would only require the PC/laptop to render a small portion of the map, hence the load is smaller. Even better: Add an unassigned player and switch to that perspective. The unassigned player will never explore or expand, so its field of view would be limited to just the starting civic centre.
Related forum thread - Is it possible to run 0 A.D. in a "server-mode"? Or otherwise consuming less resources when only hosting? (20/Apr/21)
Optimal GFX settings To achieve an optimal balance between nice graphics effects and enough performance for a smooth game, consider this in 0 A.D. gfx settings:
(1) Enable GLSL
(2) Enable FXAA (no impact) and MSAA (little impact on performance, except for very weak GPUs)
(3) Enable water transparency
(4) Disable other water effects (reflection, refractions)
(5) Disable shadows
Related forum thread - Find optimal gfx/ game settings? (1/Jun/21)
Multiplayer related
Registering for the Game Lobby does not work:

- "Certificate expired"
- "The stream has been closed by the server"
- "An I/O error occurred
Try to disable TLS via Settings => Options => Lobby

Worth mentioning: there is a limit to the number of accounts you can submit per hour; if it doesn't work, try again later.
"Authentication Failed" This message usually appears, when you have got a typo in your password or username. If you are sure your password is correct, you could create a forum account and contact user1.
The multiplayer lobby is empty. You are probably using an older version of the game, see for the latest version.
How to play online? Go to Multiplayer --> Game Lobby --> Create a new account, then you should see this page, now you can join a game or set one up yourself via Host Game.
I forgot my Game Lobby password. Resetting is currently not possible via the user interface, you would need to create an account on the forum and contact user1.
How to play via LAN? See this forum thread with detailed instructions - Multiplayer on LAN (16/Jan/17).
My friend cannot join my game and I cannot join their game. Firewall:
Try disabling it or add an exception for 0AD.

If you forward the port, everyone will be able to join you. If you use STUN when hosting, probably many but not everyone will be able to join you. If you can't join someone else's game, there's nothing you can do about it other than informing the host that he should port forward or host your own game.
What is port forwarding UDP 20595? A port forward is a way of making a computer on your network accessible to computers on the internet, even though they are behind a firewall/ router . It is commonly used in gaming, security camera setup, voice over ip, and downloading files. After you have forwarded a port you are said to have an open port. 0 A.D. uses the port 20595 by default.
How to do port forwarding? This can be adjusted in your router settings, try googling the manual of your router and follow the instructions from there.

Platform-Specific Troubleshooting

Issue possible Solution
Linux related
How to install 0 A.D. on Ubuntu? See this forum thread - How to install 0AD 24 in Ubuntu? (3/Jul/21).
Game does not capture my left ctrl key press. The left ctrl problem seems to be a result of the show cursor functionality of gnome-tweak.
Related forum thread - Crash on map selection and hotkey problem (19/Jul/21)
macOS related
0 A.D. cannot be opened because the developer cannot be verified. The reason for this message is that 0 A.D. would need to be signed with a developer AppleID, which costs an annual subscription. At the moment, this problem can be bypassed for the installation by right-clicking and clicking Open.

Related forum thread - MacOS Catalina requires notarization (4/Jun/19)


Question Answer
How can I contribute? Look here. You can also introduce yourself on our forums or dive into our IRC-channel #0ad-dev on QuakeNet.
There are basically four important channels:
(1) - managing bugs and the wiki
(2) (aka Phab or Phabricator) - managing/ reviewing patches
(3) - discussion/feedback/miscellaneous
(4) - translating the game
Can I help testing the development version? Yes, testers are always welcome. It is recommended to join IRC (#0ad-dev on Quakenet) to discuss things more easily.
Most of the time the developers are happy to point you to a patch that needs testing and that you can give feedback on.
If I find a solution to a bug, what should I do? We use Phabricator to manage patches. You can upload your solution there and request the review of your patch. If the developers accept it, it is added to the development version and later ends up in the bundled release version.
Important: The only thing that gets a patch committed is a team member who pauses work on their own feature to review something. So if you feel you are not being heard, you may need to nag a developer, the best way is usually via IRC 0ad-dev.

Where and how should I report bugs?

See wiki/ReportingErrors
Before creating a ticket, you are encouraged to do a quick search, as the issue may already be known. You can use the search box below to search all tickets (open and closed) by title.


Question Answer
How to beat the AI and get better in this game? Read these forum posts and you will defeat the AI and most likely become a competitive player in the Game Lobby:
- Multiplayer strategy guide (11/May/17)
- Civ analysis for A24 (12/Mar/21)
- Ultimate guide on how to win in A24 with Persians (8/Apr/21)
Alternatively, you can watch Youtube replays (see Miscellaneous below) of pro players or download their replays to better see their build order and which tech upgrades they focus on.
You can find some replays for A24b here: Feldfeld's replay dump (25/Feb/21)
What is the difference between Random, Skirmish and Scenarios? Random: All settings can be adjusted.
Skirmish: The number of players and map size is fixed, everything else can be adjusted.
Scenarios: Settings cannot be adjusted, everything is fixed.
How can I ban observers in multiplayer mode? (1) You can set up a password when you host a game.
(2) In the settings under General, find Observer limit, set it to zero and no one can join after the game starts.
(3) Open the chat window and type /kick (person can rejoin) or /ban (person can't rejoin) followed by the user nickname. Only the host can kick out observers.
How to enable mods? See wiki/Modding_Guide
What does the triangular icon above my unit indicate? It shows the current rank of your unit. The bar increases during combat, when it is filled, its rank increases automatically and your unit becomes a better fighter, but its ability to gather resources decreases. The Rank icon and Experience status bar can be toggled on/off in the Settings on the Game Session tab.
Can I order my units to run? No, the unit only runs when it flees and when it is called into formation. There is no specific function that you can use to command a unit to run. See forum thread - Walk vs. run (20/Jun/21).
How do you destroy a building instead of capturing it? Click with the right mouse button while holding down the ctrl key on the building you want to destroy.
How does capturing work? The buildings have capture points for all players. If a player reaches 100% of the capture points for that building that player gains control over that building. Capture points can be gained by ordering units to capture that building or by that building standing inside a players area of influence (the player-coloured borders).
Where can I find all keyboard combinations for the game? (1) Either in the game itself via the GUI Hotkeys button or
(2) see wiki/HotKeys.
How do I find idle units? (1) You can just press . or
(2) there is a button right below the minimap.
How do you select all idle workers? Press Alt + .
How do you select only military units? Press Alt and draw a rectangle over your units.
Can you make groups of units? Select a bunch of units and then press Ctrl + 1, you can make more multiple groups by using different numbers. To select this group, press the 1 key or another key to which you have assigned your group.
How does trade work? Either you build two markets and have traders run from one to the other or you send your traders from your market to one of your allies, the latter being more lucrative. Docks can also be used as market destinations.
Via the menu Barter&Trade you can set what is traded by clicking on the up or down arrows for each resource.
Does the game have cheat codes? Yes, they are all listed here: wiki/Manual_Cheats.
How can I get units to move as individuals and not in formation? Click with the right mouse button on the symbol at the top left, the small indicator changes the symbol.
How can I change the maximum/minimum camera zoom? In single player mode, you can open the developer overlay with Alt + D and toggle the Restrict camera option so that you can adjust the camera zoom to your preferences.
Where do I get a rating and how is my Game Lobby rating calculated? Currently, only 1v1 are rated and this option can be switched on/off by the host of the game. When the option is turned on, you will see it at the bottom of the game setup page.

[NEEDS MORE EXPLANATION, it uses ELO like chess, but more details would be nice]
How do I report a user who quits a rated game without resigning? You need to find the correct replay file (see wiki/GameDataPaths) and upload it here: Ratings Disputes and Offence Reporting (27/Mar/16).
How are the total, economy, military and exploration score calculated? (1) Total = Sum of economy, military and exploration score
(2) Economy = Resources gathered + trade income, divided by 10
(3) Military = Sum of enemyUnitsKilledValue, unitsCapturedValue, enemyBuildingsDestroyedValue and buildingsCapturedValue, divided by 10
(4) Exploration = percentMapExplored, multiplied with 10

Map making

Question Answer
How to get started? The game comes with a Scenario Editor (aka Atlas) for information see wiki/Atlas_Manual and Scenario Design/Map making in our forum.
Can you recommend a video? This tutorial was made by a Youtuber called Tom0ad - How to easily turn ANY Country into a 0AD Map! - 0AD Map Making (28/Mar/21).


Question Answer
How to get started? The game itself is developed to be highly modifiable, to get started see wiki/Modding_Guide and wiki/Mod_Layout.
Taking a look at small existing mods (e.g ffm_visibility or Battle Mod) might help to better understand how things work.
Some total-conversion mods are: Hyrule Conquest, Delenda Est or 0AD City Builder.
What to do if I need help? (1) You can ask via IRC 0ad (general questions) or 0ad-dev (technical questions).
(2) You might find old threads in the Game Modification subforum answering your questions, otherwise you can create a topic and ask for help there.
Can I use the game assets? Yes, you only have to comply with the 0AD license.
"0 A.D. is released as open source: you can freely use, copy, modify and distribute the game's source code and data files, as long as you include attribution to Wildfire Games and let anyone freely modify and distribute any of your own modifications to the game's files."
Where to find the source code? Here you can find all the information on how to get the source code and build the game: wiki/BuildInstructions.
Can I add my mod to the in-game download area? Yes, you would need to upload it to, just follow the instructions from here: Guide for publishing mods on (13/May/18).


Question Answer
When will the game be released? When it will be ready. Unfortunately we can't be much more specific than that, there are too many things we just don't know. We're working on the game in our spare time, so we don't know how much time we'll have to make the game. We've never developed a game before, so we don't know how long it will take to do one or the other.
Why is this game still in alpha? A developer wrote (21/Mar/21): "0 A.D. is also still quite laggy, and needs a fair few improvements before I think it's ready for a more mainstream audience. I would push towards dropping the 'alpha' from the name, but that doesn't mean it's quite ready."
Will you put the game on Steam? We're going to look at putting the game on Steam to make it easier for people to find out about it, but not until we get to the beta stage at the earliest. We want the game to be as good as possible so people don't miss it among all the other games that are there.
Is the website up to date? Yes, but gameplay related infos (Features, Factions, Game Manual) are a bit outdated. This needs to be fixed, if you want to help us, raise your voice either via the forum or IRC.
How to keep up with the game? For casual players there is no channel that summarizes progress. From time to time there are some social media posts and a development report, but they are rare.
For players with technical background, you can read the Changelogs, check committed patches on Phabricator or the timeline on Trac.
Does 0AD use any social media accounts? You can find a list of all accounts at the bottom of our homepage
Are there Youtube channels about this game? The four most popular channels are:
- 0AD Newbie Rush
- Ágora 0AD
- Tom 0ad
- ValihrAnt - 0AD & AOE2
Does 0AD have a Discord? There is no official Discord, but there are unofficial servers: --> Related forum thread: About my Discord for compettetive 0ad players (1300+) (25/Jul/21)
How about more factions? There are mods that add more factions to the game (see
Likely candidates: Han Chinese (20/Apr/21) , Zapotecs (7/Apr/17) and Nomads Xiongnu(29/Apr/17)
The concerns, for adding new factions, mainly revolve around balancing all the factions so that they are equally strong, but still different from each other and to be historically accurate.
Will you add single-player campaigns? It has been committed to the development version with changeset 24979 (2/Mar/21), you can find more information in this forum thread Tutorial Campaign (29/Jan/21).
Mapmakers who are willing to work on a campaign, please contact us (via forum or IRC 0ad-dev), we would appreciate your contribution to the implementation of the campaign or a tutorial.
Does the game have an in-game store, is it freemium or pay-to-win? No, everything of the game is totally free and open source. We only use donations to pay for server hosting, etc.
Would it be possible to have access to old versions of 0AD? Yes, on this page - - you can find all released versions and some statistics about how many times each version has been downloaded recently.
Can you recommend a presentation or video about 0ad? (1) PDF-presentation - Sogyo Presentation (1/Feb/20)
(2) Video - 0 A.D. Empires Ascendant, a FLOSS Game (25/Nov/20)

(3) Video - 0 A.D. Evolution - All Alphas (3/Feb/19)
What to do if I have a question that is not part of this FAQ? Join IRC 0ad (general question) or 0ad-dev (technical question) or see help & feedback section of our forums many other questions have already been answered. You may also ask any new questions there.
Last modified 4 days ago Last modified on Aug 1, 2021, 7:17:58 PM

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