Be prepared. The LS you see in the screenshots has defeated Vrtra. Unfortunately, however, they wiped to Ouryu. Near win though. I've been following the Japanese BBSes About this and so far have heard of two wins. But, some of the Japanese BBSes have been known to have false information before, so take it with a grain of salt. I'm sure someone in your LS can translate the following for you, it gives drop information as well as fighting tactics (assuming it's not made up).
http://bbs.2ch2.net/test/read.cgi/ff11job/1111133994/801-900
Report 1:
Ouryu倒ã—ã¦ããŸã€‚
土エレã¯é»’ãŒå‡¦ç†ã€ãƒŸãƒŸã‚ºã¯ç‹©ãŒã‚¿ã‚²ç¶æŒ
水エレã¯å¿ãŒã‚¿ã‚²ç¶æŒã—ã¤ã¤ã‚¢ã‚¹ãƒ”ルタンク&狩ã®ã‚¯ãƒ©ã‚¯ãƒ©ç”¨TPタンクã«
ã—ã¤ã¤ç«œãŒé™ã‚ŠãŸæ™‚ã«ã‚¹ãƒ©ãƒƒã‚°+é™ã‚ŠãŸç›´å¾Œã«é€£æº+MBã§åœ°å‘³ã«å‰Šã‚Šã¤ã¤
45分ã§æ’ƒç ´ã€‚
ドãƒãƒƒãƒ—ã¯ä»Šå‰£ã¨æ˜†å¾çŸ³ãŒ4個
経験値ã¯ãªã„。称å·:應é¾èª¿ä¼çŒ›å
竜慣れã—ã¦ã‚‹LSãªã‚‰ä½•å›žã‹è©¦è¡Œã™ã‚Œã°å‹ã¦ã‚‹ã¨æ€ã†ã€‚ãŒã‚“ãŒã‚Œã€‚
http://bbs.2ch2.net/test/read.cgi/ff11job/1114737562/601-700
Report 2:
アットワコースENMã§æ‰‹ã«å…¥ã‚‹çŸ³ã‚’リヴェーヌAã®é’モヤã§ä½¿ã†
応竜フルアラBCã„ã£ã¦ãã¾ã™ãŸ
1回目 4ï¼åˆ¶é™ã ã¨æ€ã£ã¦ã„ãŸãŸã‚1ï¼äººãらã„レベル5ï¼ä»¥ä¸‹ã®ã‚¸ãƒ§ãƒ–
    ã„ã£ã¦ã¿ã‚‹ã¨ãªã‚“ã¨BC内ã¯ï¼—5制é™ã€å½“然瞬殺ã•ã‚Œã¾ã™ãŸ
2回目 全員メインジョブã«å¤‰ãˆã¦ç‰¹æ”»ã€‚敵ã¯å¿œç«œã€ãƒŸãƒŸã‚ºã‚¨ãƒ¬æ•°åŒ¹
    飛行形態時ã€ã‚°ãƒ©ãƒ“デマラソン。地上時ã€ã‚¨ã‚¢ãƒï¼”スリプル2
    ã§æ™®é€šã«å‹ã¦ã¾ã™ãŸã€‚ãŸã ã—黒1ï¼äººè¿‘ãã„ãªã„ã¨å‰Šã‚Šãã‚Œãªã„ã‹ã¨ã€‚
    é éš”ã¯ã»ã¨ã‚“ã©ãã‹ãªã„。後åŠã‚ªãƒ¼ã‚«ãƒ¼ã§ç¯„囲7ï¼ï¼ã‚’連発ã—ã¦ãる。
    ガãƒã¯ç„¡ç†ã€‚ベヒ99BCã®è¦é ˜ã§ã‚„ã£ã¦ã‚‚楽ãã†ãªæ„Ÿã˜ã€‚
  
ドãƒãƒƒãƒ— å…罪符 海霊胴 地霊胴 真竜角
Even some responses on that forum are talking about how they wonder if the drop information is really true, however, so like I said take it with a grain of salt. For the curious, total combined listed drops for the two reports is Wyrm Horn, Aquarian: Body, Earthen: Body, Imanotsuguri, 4 Kunwu Ore
At the current time, the only confirmed (screenshot) battle report is Opeth's linkshell almost winning, but not.