Ki and Gil will enter this room through either the door at the top-left of it (if they came from Rest Room) or the one down at the bottom-left of it (if they came from Large Hall). It contains a total four Orange Bats, four Blue Knights (which have red eyes) and eight Black Knights (which have red visors).
The key at the top of the room opens the aforementioned door at the top-left of the room, the key at the top-right of the room opens up the door at the bottom-right of the room, and the key at the bottom of the room opens the aforementioned door at the bottom-left of the room. (The four Orange Bats might make them difficult to collect, however). There is no key for that door at the top-right of the room - so there is no way of knowing where it leads.
The aforementioned door up at the top-left of the room leads back to Rest Room (Room Pass: 2C7), the door at the bottom-right of the room, like the one at the top-right of Water Line, leads to Colosseum (Room Pass: HC2), and that aforementioned door at the bottom-left of the room leads back to Large Hall (Room Pass: DV7). You should remember the second of these Room Passes - as the first and third of them will be of little use to you now.
