This is my first encounter with the hydra fight. Last night I tried a couple rounds and another today. All times (so definitely reproducable) was able to cause the ebon head to submerge, then defeat the other three heads. I get the message that he has resurfaced and "get him!" He is visible on normal view but not on the battleboard, thus untargetable. Other heads will also move to his spot and it will look like two heads on top of each other.

Strange thing that happened today was Rooster Cogburn on two occasions hit the submerged ebon on a double tap attack (this was while fighting the other three heads after ebon submerged). Rooster was the only one who could see him at that point! I don't know if there are more problems besides this as this is the first time for me on the fight and I am unable to progress.

Just Another Pirat... on Aug 1, 2014 wrote:

This week's mantenence seems to have cured some ills. Last night I was able to complete this fight, the ebon head was targetable! Due to poor strategy on my part I did have to hire a henchman to save my sorry hide. But once that hired privateer got me to stop standing around with my head wobbling it was interesting and a fun fight. I'll have to go back later for rematches, surely that scaley beast has more loot than a single piece of cheese?

Very well written and I just loved the giggles. Yes Ratbeard has mentioned that the loot tables are just another bug with the Hydra. Hopefully they will squash them in the next update.