>> Sr. Ninguém:

“I wanted to try that farm game a while back... now, how do I get rid of it?”

Just don't play. If you have something planted, or empty plots, it'll send you some messages, but only once. After that, you can forget about it.

Regarding @mentions, they're unnecessary. When you create a new post (not a comment to a note, like you did here), you have the "To" and "CC" fields, where you can add the names of whoever you wish to "tag" in your message. Or even make the message private, by removing the "Followers" from the "CC" field. Etc.