This season is all about the weird ass groups that are only loosely attached to any house or king. I get the feeling they're trying to set the world...
If that's the case, then as cool as that crypt set was it was confusing as hell. They were looking down into bars in the floor and talking about who...
I watched the episode twice, and right before he talks about the Targaryen who drank wildfire he definitely talks about a dragon who belonged to one...
I'd buy 100 years since there were dragons, but Joffrey still talks about that one under the floorboards as if it happened after Robert's rebellion....