A planet with a massive metal core, rocky, with a diameter almost as large as the Earth, yet the mass is slightly higher. Gravity is close to Earth's, or even slightly higher. It revolves around its red sun in 58 hours, but it turns to it with one side and there will be no change of day, at least on the surface. Since it has the metal core, it has the magnetic field. 

 The atmosphere is dense, tens of Earth's atmospheres (on Venus ~ 92 atm.). The composition is mainly carbon dioxide, nitrogen, sulfur oxides, sulfuric acid, as well as hydrogen sulfide, mercaptans (RSH), dimethyl sulfide, perhaps a bit of nitrogen oxides, there is practically no water. 

Surface temperature fluctuates between 320 C and 405 C in the central regions of the illuminated and dark hemispheres of the planet, respectively. In the area of the terminator, the temperature is about 365 C. A few kilometers above the surface, the temperature levels off due to strong winds, and also gradually decreases. Most of the life forms are concentrated in cloud layers at an altitude of 40 to 55 km. In the upper part of this layer, the pressure and temperature are close to Earth's. There are two variants of biochemistry with solvents in the form of dimethyl sulfide or sulfuric acid. Some organisms can switch from one to another. Flying organisms with sulfuric acid can sometimes descend (dive) into the lower atmosphere. The melting and boiling points of demytyl sulfoxide {(CH3) 2SO} 18C and 189C, respectively, and sulfuric acid (H2SO4) 10.4 C and 337 C. 

To explore the hottest regions of the daytime zone, as well as tectonic faults and areas of long-term volcanic activity, the intelligent creatures created bioforms (biorobots) with liquid sulfur as a solvent (melting point 112.85, boiling point 445 C). These creatures are used to extract valuable mineral resources from the planet's surface. 

Due to fumaroles, this huge biological structure rises from the bottom to the surface of the ocean. It is based on chemosynthetic organisms, while there is a floating forest, or rather a jungle on the surface of the ocean of Avalon in the area of perpetual noon. These two complexes, chemosynthetic and photosynthetic, are connected by an intermediate structure that has no analogues in Earth biosphere. It consists of powerful trunks intertwined with each other, grooves and ribbons with chains of numerous float bubbles supporting them. In the areas of fumarole smokers, nodules of various metals, including the rare earth ones are formed; and organisms that accumulate almost the entire periodic table in their skeletons also live. Thus, these oases are a source of important resources for the intelligent life on this planet.