Sure, the strategy that worked best for us was SCH/RDM (me) and RDM/NIN duo. SCH should be replaceable by BLM, probably smartest to /NIN as BLM. I buffed up and activated Desert Boots with Sandstorm, casted Helix on it, and pulled it to Arrapago Reef zone. I would normally do my best to get a clean pull and avoid other mobs until Aynu deagroed, but even with adds, they would normally deagro along with Aynu, so I could run back to him, tag him with Bio II, and run the rest of the way to the zone, where the RDM was waiting and zone. I've done this with 2 RDMs, one with W. legs, and one without. The one with would run the pull with me snk/invis and when Aynu deagroed, he'd Bio II him and run him the rest of the way to the zone.
Once there, the RDM's sole job was to keep Bio II on Aynu, while I on SCH provided all the damage through helix. RDM would Bio II Aynu whenever it was almost up, zone in Reef, and then I would zone into Caedarva and Ebullience helix Aynu and zone. Helix was a good choice over nukes since it would cover any breaks it Bio that would happen, but if your RDM is able to keep Bio II up at all times, then nukes instead of helix can be used.
Once it got to around 10%, zone into Caedarva and time nuke together your best nukes (make sure it's not Ice magic), and it should kill Aynu off. If you have a THF for TH, have him attack Aynu right before the nuke, with shadows and evasion gear he should be able to survive the few seconds until Aynu dies.
Always make sure to have Stoneskin and Utsu/Blink up and casting from absolute max distance when zoning Aynu, as I've died in the zone from being just a tad too close more times than I can count.
We tried straight tanking it with DNC or THF, perhaps could work with WHM or RDM, THF or DNC, BRD (BRD is the missing element that we never got to try, but I think it would be very helpful.) This strategy never worked for us, so we kept with the DoT zone strategy, which was normally pretty successful, barring any freak accidents. Good communication is key for the zoning method though, knowing when your teammate is zoning, and when it's safe to zone in is crucial.
I hope this helps, I absolutely love the dagger, and hope that it doesn't suddenly become outdated with the level rise after I just managed to get it. >.<
Edited, Jun 15th 2010 9:08pm by apresmoi