No. Since update 1.206, mods do not make a Space Engineers server experimental. Keen Software House, the game’s makers, wrote: “Mods are no longer experimental. Players who want to play with mods don’t have to turn on experimental mode if they don’t need it.”
Other things do, and a new server on Loafhosts already has some of them. Its first world has in-game scripts on and Block limits on None, and the game counts both. So players of a new server need Experimental mode in their game (under Options, Game) with or without mods. Adding mods changes nothing about that.
Experimental mode is a game setting for features Keen counts as unstable. The game decides it for each world from the world’s settings.
What does not make it experimental
A long mod list, or a mod that adds blocks, ships, textures or planets. The five mods in the picture are on the list and loaded, and they are not a reason on their own.
- Loaded at the last start
- On this server
What does make it experimental
- In-game scripts. The Programmable block scripts switch in World settings, Players group. Its help line says “On marks the world experimental”. A new world has it on.
- Plugins. A plugin is an add-on the server loads. The panel tools are one: with Panel tools on, the server is experimental. See panel tools.
- Block limits and PCU. Block limits set to None, or a PCU limit above the game’s own mark, are marked in the Config Editor’s help lines. PCU means performance cost units: how much may be built. A new world has Block limits on None.
- Other settings. Keen names permanent death, spectator mode, three mechanical-block settings and unsupported stations. The game’s list is not closed.
- The server’s hardware, when it is below Keen’s minimum. Not checked: whether the 2 cores of a Small plan count as below the 3 logical cores Keen names.
- The world’s Experimental mode row. It forces the mode on and cannot force it off.
Mods with scripts
Some mods contain scripts of their own. If a mod’s script does not compile at the last start, the Mods page shows a note naming it, and the row says “Loaded at the last start, but its script did not compile, so what the script does is missing.” Update the mod or take it off the list. See script did not compile.
Find the real reason
- Open the Console after a start.
- Find the line
Experimental mode:afterLoading session. If it says Yes, players need Experimental mode, whatever the mods are. - The line under it,
Experimental mode reason, lists why.
The start log of a new Star System world on Loafhosts reads Experimental mode reason: BlockLimitsEnabled, EnableIngameScripts, Plugins. The last one is the panel tools. Your list depends on your world.
The mode ends only when every reason is gone: Panel tools off, Programmable block scripts off, Block limits not None, the PCU limit and the other limits inside the game’s safe range, and the world’s Experimental mode row off. Turning off one of them is not enough. See turn off experimental mode.
Not checked with a player on 1.210 as of 15 November 2026: what a player in safe mode sees when they try to join an experimental server.
If it does not work
- Players still need Experimental mode with only mods. Read the reason line in the Console. On a new server the scripts and Block limits are enough.
More about the game: Space Engineers servers on Loafhosts.
Sources: support.keenswh.com: Update 1 206 fieldwork, spaceengineers.wiki.gg: Experimental mode, spaceengineers.wiki.gg: Mods