Not really. Games have very similar security implications as any other server/client software.

You are right now reading on exactly such a system, which is open source, and still you don't see massive amounts of hacks targeting lemmy or piefed.

The premise is simple: Never trust the client. The border you have to defend isn't the border between the client software and the user, but the one between the client and the server. Always treat the client software as compromised.

In terms of games that means:

• All game state calculation happens on the server. The client sends to the server what it wants to do, the server sends what happens. So instead of the client sending "The player is now at position XY", it sends "The player is walking forwards". The server calculates the speed, distance and new position and returns that to the client.
• The server only sends the client things the player should know. If the enemy unit is not visible, it is not sent to the client.