In the sentient levels, the goal is to prevail over active motes of various types that hunt and absorb other motes, including the player. Hunting them typically involves absorbing as many inactive motes as possible before chasing down the active ones with the extra mass one has gained.
S1O - artificial life
S1O1 - Absorb the Ovarium
The Ovarium is the first cell that you will encounter. It will attempt to move towards other cells, but will also try evading any attackers. It only shoots motes at a slow rate.
On the normal map, try moving downward to collect the blue motes. When you are large enough, which shouldn't take too long, return to the ovarium and try to claim it.
S1O2 - Absorb the Biophobe
The biophobe won't attack other motes, but if a larger mote gets too close, it will rapidly fire motes in an attempt to escape.
S2O - survival of the fittest
This level has many Ovariums and motes.
S2O2-Absorb the Nemocyte
This level has a Nemocyte, a fast, agressive mote that speeds away from danger.
S2O3-Absorb the three Nemocytes
There are three Nemocytes here, and all must be absorbed.
S3O - deadly ecosystems
Multiple Ovariums and Nemocytes make this place hazardous.
This level replaces Ovariums with large, inactive motes.
S3O3-Absorb the Ferax
This level contains the Ferax, which ejects big motes at a time to propel itself quickly. Players should zoom out, and observe how sentient it is.
To beat it, try slowing down time, resetting (not randomizing), and memorizing the biggest and closest inactive motes you can absorb. Once big enough, go after the Ferax when both are at near equal, but the player slightly smaller sizes with a mote in between. The Ferax will panic the moment the Player is bigger (by absorbing the middle mote), and you can use the extra size to propel behind to chase it.