I am from AscendantSky LS (too bad AS wasn't on this website point system long long long time ago ; . We were first to kill Tiamat, and we did it with only 1 BST and no main SMN. We kill this with 24 member and it can be done without drowning it with BST.
Vytra - my LS (ascendantsky) and Asa's LS SoulofCrusades (JP LS formerly known as NewCompany from midgar, I think midgar?) teamed up to take Vytra and we had 109 members. You cannot kill this witht he numbers a guy on another post said. We were among the best (top JP LS is NewCompany server wide and AS has been the first to do almost everything, we were week behind GO on Kirin) there was an could not defeat this. A alliance of I believe 85 took Vytra down on Fenrir twice now. That picture someone posted was from Fenrir. They got 4 cloths for the Bard JSE body on each kill. So far that is all they know it drops. Killing it with 40 people is impossible like a guy on here said.