d0f74f4b_ions_and_Hints___Team_Ico_Wiki__Dormin_s_description
[Colossus] Hydrus [Hints offered during battle] Swim on the lake surface to draw out the colossus... [Dormin's description] 
Thy next foe is... A ruin hidden in the lake... A ripple of thunder lurks underwater...
Dormin's Colossus Descriptions and Hints - Team Ico Wiki
Dormin's description