After the first Clambo, ascend and go left through a false wall to find the “K” letter along with an Enguarde crate. Pass a DK Barrel and you’ll see Clambos shoot pebbles in different directions. The “O” letter is in an opening above a school of green fish. Pass some Clambos and you’ll find the next DK Barrel by a blue shark. Go by a school of blue sharks and you’ll find the Star Barrel. Pass some Clambos and you’ll find the next DK Barrel. Ascend by some bigger sharks and you’ll find the “N” letter by the left wall. After an arrow sign, pass some Croctopuses and grab the “G” letter below a Clambo shooting pebbles in 5 directions. After you get the last letter, go to the exit.