[DeltaMasterMind]

Ok so the dragonic bloodline is powered by this pick: cSorDracon
To do what you want to do you need to make a list of dragons appear will involve adding some "things" (races or something off like custom racial quality may work) and for each dragon type you want listed add in the description text box of each dragon type you make available. Then add in the tags Selection.DragonDisc and the associated BloodEner.(energytype) that goes with the dragon. Basic energy tags are Acid Fire Cold Elec. This is the simplest way I could think to do it as the whole dragon bloodenergy thing has alot of different scripts and call logics in it.

P.S. Take with a grain of salt as I spent 8 minutes digging to get you this info and I have not tested it myself. The racial special is xHIDDragon that does the underlying scripting for the bloodlines, but as I read it I didn't see how it's custom expression was actually doing anything that I could understand. So I wrote the above as a possible catch-within setup that may use the predefined logic.