New"sub-biome"for the nether(combination of basalt deltas/soulsand valley)

This biome could generate only when a basalt deltas biome generates near a soulsand valley

Also this biome should have obiusly the same blocks of the original biomes but "mixed". Another thing to say is that instead of those "basalt stalagmites" it should generate "basalt stalactites" from the celling 

I based this idea from the final scene of the 1.16 trailer where you can see (in the atmosphere) what im talking about.