Board Thread:General Discussion/@comment-28172712-20160410032410/@comment-1500935-20160414011454

Frankly I don't know, both could have been the original biome. /:

Btw I just noticed that the old development map for the Lost River already had the second Blood Kelp Zone already marked on it, although the Bones Field has been placed differently:

400px

The arrows seem to suggest there will be entrances to the Inactive Lava Zone in the other chambers.