Developed it for Ludum Dare 33.

Control the tentacles to destroy the ships through the sea. 

How to play: 
Press ESC to open the menu and check the skills you have learnt. 
Left click anybody you want to kill to attack it with one of your tentacles. 
Right click anywhere to cast the skills. 
Use mouse wheel to switch your current skill. 
Your dead tentacle will raise up after a while. 
When they are all dead,  game will be over. 

Engine: Game Maker Studio 
Graphics: GIMP, Spriter pro 
Sound: Most are made by ourselves using BFXR, Audacity and so on. 
Text edit: Sublime Text 2 
BGM: They are all from the humble game making bundle.