GoodMorningCosmoteer The way that multiplayer works is that everyone's computer is running the entire game simulation and constantly comparing the results with each other to make sure they've simulated it in exactly the same way. If one player cheats in such a way that their simulation computes a different result, then a desync will happen and the game will pause for a few second while it resyncs. (It assumes that the host's simulation is the "correct" one, which does mean that the host could potentially cheat, but not without causing a desync.)
And to be clear, if you get a desync in a multiplayer game, it's extremely unlikely that someone is cheating. Desyncs primarily happen because of bugs in the code, which I am slowly fixing.
There are also other, fairly minor ways in which players could cheat that don't change the game simulation. These are things like removing the Fog of War or enemy ship roofs. These "cheats" would give that player an informational advantage without actually modifying the game simulation. (Those kinds of cheats are probably not a big deal in Cosmoteer -- they're much more of a problem in traditional RTS games like Starcraft.)
