just registered just to note:
You don't need a mantis crew member to get the mantis cruiser. Just did that. (What a relief.) Just Medbay and Transporter. The first blue option, which you only have with a mantis crew member is optional. That can also be seen from this source: http://ftl.wikia.com/wiki/Legendary_thi ... ndom_Event
Thank you, this really helped me. It seems like this is exactly what I was looking for.