Blue Eye button? If you mean the part with swinging axes, you need to hit the glowing orb with an arrow next to the dead ninja. It will reveal an invisible path, be careful.
*You need to drain two waters *Defeat 2 worms down deeper in the Aquaduct inside a cave *When you enter a room filled with a BIG Statue and water flowing, if you enter the room with hallway and enemies respawing. You need to run all the way to the end of the hallway. You'll see some sort of a block, perform flying bird flip and hit the block.
I assume you have the insect key, now go back to the room with no stairs, use the wall/corner run to get up on the platform, (some bricks are sticking out)
once you get up, turn right and opent the door of insect.
I had this problem too, I figured it out after a while though.
DUDE IM IN CHAPTER 16 NOW... WHR SHOULD I GO TO FIND THE BIG BOSS ENEMY... I SEARCH ALL AROUND BUT COULDNT GOT ANY ENEMY... IS IT AT NINJA FORTRESS... IF HOW IM GOING TO THE FORTRESS.
here, just go out the same way you entered, u should be back on the streets, not in the sewers.
now find your way to the serpent statue you saw at the beginning of chapter 3. place the tablet pieces on the thing and u'll find yourself teleported to your village. now go to the place where Rachel used to teleport, use it and you should be fine from there.
