<Snipped quote by Fallenreaper>
Should I make my entrance separate from the collab post and then join in that once the entrance has been posted? I ask because I have some backstory stuff I want to get in there with the entrance and I'm not sure it would flow very well in the collab.
In cases like this, I suggest using your best judgement and follow through with it. Which in this case, it might be ideal so we don't have random mention of things that don't relate and then abruptly shift back to the scene. That's part of the reason I wanted everyone to do a intro post first so they could get everything not directly related to the plot done and set up their PC to just hop in. It makes things easier normally.