Baatsalia
A large part of Baatsal life takes the form of apparent craggy rock, appearing quite unremarkable. The yellow gas comes from internal organics dissolving in the acid from slabs fractured in the last few hours.
Baatsalia is a domain of life from the planet Baatsal in the Gigyanshi system, sector T54-Y21-Z41
It is silicon-based life in a sulfuric acid world, and for a time its status of being alive at all was disputed.
The lifeforms create communal colonies of silicon-compound slabs that resemble rock; however the slabs are relatively low-density, porous, and elastic. They float and grow on sulfuric acid seas, eventually outgrowing their structural integrity, at which point they begin to tear and fracture.
Due to their porous nature and sources of food, sections of the lifeform colonies slowly increase in density over time, eventually accumulating enough material that their density surpasses that of the acid sea. At this point the dense section will be separated from any larger colony it is a part of, after which it sinks and dissolves, adding its constituent resources back into the environment.