[Charles Martel]

Looks like a lecture illustration of a Thagomizer:

Poor Thag, he really had rotten luck.

[SpinnerWebb]

It really is... a Thagomizer.

[rjsimmon]

Thag, my pre-historic ancestor, never really had a good relationship with the local wildlife. First the bear, then the Stegosaurus. And no one wants to talk about that Pterodactyl incident...