You while flowing in that river (refer to part 1) got discharged into the ocean, after some convections, you landed on...LAND?! You have got to get back to your... home?, well, it is better than turning to ice and waiting for global warming to melt you, right? you are trapped somewhere in the south pole and must get back, you find a green crystal (the goal, lol) that should let you go to another waterbody, maybe the Carribean sea, who knows... but its better than freezing!