Echelon Expansions titles provide player options, often expanding on or changing existing rules.
Draconic Bloodlines takes the sorcerer’s draconic bloodline from the Pathfinder Roleplaying Game Core Rulebook and adjusts it for each of the twenty-five dragon types in the first four bestiaries. Each dragon type has its own bloodline, with a modified spell list and a few of the bloodline powers changed to be more representative of the ancestral dragon type.
Other bloodlines products are in progress, for fey and the various outsider types. There is also a book on hybrid domains in the queue.