Otka Island

Otka Island is a location in Golden Sun: Dark Dawn

Otka Island has two things of interest and is a little difficult to get one of those two items.

To actually get to this item it is in the middle of the map a little blur close to where Izumo was the Lost Age but North.

It is here that you can acquire the Jupiter Djinn Lull for your party as well as the summon Catastrophe.

The Jupiter Djinni, Lull, is at the very beginning of this Dungeon and to get to it you need Himi as well otherwise you cannot get the Djinn nor Catastrophe because you need her Search Psynergy. Also of note you can not get Catastrophe without the Sol Blade due to it acting as a key in some parts of the game. This being said, you can still get the Djinni early.

The first 3 or 4 rooms is very easy after that it is quite difficult their is a few treasures here as well one Psy Crystal and more. The reason here is complicated is because their is no map whatsoever and Catastrophe is in the no map part of the dungeon.

One method of successfully traversing the dungeon is to use the "left hand rule". Which is a simple way to navigate any labyrinth. Traverse the dungeon by having Matthew's left hand always against a wall, will ensure at very least that you will always arrive back where you started. By using this rule from the second room in the labyrinth, it is possible to navigate the entire dungeon, collect all items, and find the exit (although Retreat Psynergy can be used here) without the use of a map. Equivocally, this works using either the left or right hand side, as long as Matthew never leaves contact with a wall.

For Catastrophe you also need to defeat a boss called the Ancient Devil.