First of all, I wouldn't see this fit as a full blog post, since it only contains random babble.
This is a Combined Fleet map with no restriction on composition. Upon completing, it will reward USS Enterprise, while also having chances of dropping Montana, Shinano and A-150 upon S-rank. The boss is , a hard-skinned installation against which Type 3 Shell has no effect.
Boss Battle Node
You may choose which direction your fleet will go. Admiral, which path will you choose? 艦隊針路選択可能！/艦隊の針路を選択できます。提督、どちらの針路をとられますか？
It is an archaic reading for 'izanai'. But they use this word when somebody is led unknown world in modern Japan. In this case the deep-sea is unknown world for human beengs, so I consider 'izanai' is collect reading.