Yeah, but it also seems really easy to make an oppressively powerful Commander deck around The War Doctor, which is why I personally have this much lower on my picks than the EDHREC crowd
If an effect exiles Fblthp from your library and then lets you cast that card, it's cast from exile, not from your library
Unlike many of the other reconfiguring creatures, it doesn't provide any other benefit or stat boost to the creature
Uses up life, pseudo card-draw, and if you're on a roll: kill your opponents by saccing all their stuff to it
The exception to this has been a number of special Secret Lair drops which included several mechanically unique cards that have yet to make an appearance in the regular game
Beyond that, there is a huge variety of general support for dodging blockers across red, blue and black: its a mechanical theme shared by ninjas, pirates and rogues across all three colors, as well as the new pseudo-type of outlaw creatures defined in Outlaws of Thunder Junction