Out of 10 games today, 6 have had griefers in them. They need to permanently ban their accounts on first offense so they're gotten rid off from the game, they shouldn't be allowed to continue playing. Ban them from even buying again. Shut them out from the entirety of their services so they can never ruin another game again.
This game is just not going to be playable if they never do anything about griefers. Harsh measures need to be taken instantly to show people they're serious about getting rid of them.