Thundercracker... If it is not a topic you want to share with a group of people I won't make you. It is a pure request you are at full liberty to deny it.

[He is concerned for Thundercreacker's well being.]

My thoughts were a general history with highlights as to what makes your world noticeably different from others, things that people could know to catch when another person from your universe arrives. It doesn't have to be anything personal.