Eerie and atmospheric. The wheely-spine 'fish' and escape-pod-looking fisherman really add to the whole effect. The music cutting out when I surface is a particularly nice touch.
I have no problem with this developer using Unity; that's their choice, but it's a serious mistake for Kongregate to select games for Badge of The Day that only a minority can even access. Leave these as regular badges, please.
This game has so much to say about human nature. Even knowing it's a computer simulation of a computer simulation, I still couldn't bring myself to leave him to die alone.