Board Thread:MHX General Discussion/@comment-4969421-20151109154146/@comment-5167887-20151130180943

So far, by observing the fight:

Ostogalore (i'll spell it this way) is a squid-like elder dragon, maybe a relative to Yama Tsukami, judging by their body structure that are a lot similar, that lives in the Dragon Graveyard and uses a blue, sticky fluid to affix bones on its back for protection. It possesses a hard shell made of bones, four arms, two mouth tentacles, and a beaked mouth with many sharp teeth inside. Its longer tentacles mimic monster heads in order to scare off intruders, and to attack. Its shorter tentacles are used like flippers to "swim" in the bones, backwards like would do a real-life squid, that's why it actually shows nothing but his back during the first phase of the fight. However it reveals its true head when enough damage has been dealt to it. (and oh boy, that's spooky)

Throughout the fight, he is able to spit its blue fluid on foes from several openings on its body. The skulls on its tentacles can be changed regularly when broken and come in 5 types (as far as i could see): Normal, Fire Field, Green Goo, Electric Fence and Heavy. As Ostogalore takes more damage, it becomes able to use Dragon Element. It can be observed when red sparks begin to flicker around its mouth. In this state, it takes some time to gather energy, but it eventually fires off a devastating red beam that is likely to 1-hit kill any hunter. The use of multiple elements may be a reference to the four flagship monsters of the title (should I say, he's Lance from the Pokémon League, lol).

When Ostogalore dies, the energy it's been gathering seems to become unstable as you can see it releasing all its dragon power towards the ceiling of the cave in a spectacular blast before it dies.

Just summing up this.