You have arrived on planet Darwin IV. Looking around you realized that you no longer understand anything: due to the lack of large water bodies, its environment is predominantly arid, dominated by vast deserts, grasslands and with huge mountain ranges and long tundra around the poles. However, it still has small patches of forests, aquifers, as strange environments as the amobeic sea, and even by the density of the atmosphere the sky makes this its own environment...

The first thing you decide to explore is the zone around the Amoebic Sea. Imagine your surprise when you saw... A huge creature that looked like a heart with tentacles... Hmm... This creature is called Sac-back. And it just calmly walked along the seashore.