I just had a look at the Casual Version of the game. When the game ends, part of the message says

"Prepare to face even greater challenges in the full game, where knife-throwing dwarves, a thieving pirate, and a fire-breathing dragon await."

This is slightly misleading, because the dragon is in Casual Cave, and does everything he does in the regular version.

The Pirate is also there, although he doesn't steal anything. But the way the message is worded seems to imply that you haven't seen him yet.