Steve Barlow & Steve Skidmore 
EDGE 
I, Hero Quests: Atlantis Quest 2: Ocean Alliance

Triton, the evil King of Atlantis, is sending his forces from a lost underwater city to the surface. He wants to take over Earth! Your quest is to defeat Triton, but first YOU must battle Hydros who is attacking a secret base on a volcanic island. Use your super-sub, Barracuda, to defeat Triton before he can complete his mission. You are the hero of this book. Only you can decide your own destiny…