Robert the Strong was a famous hero during the Fourth Age who battled against the Dragonkin and forced them into hiding. During A Tail of Two Cats, a cutscene shows Robert slaying one of the Dragonkin in their castle after it kills his pet panther, Odysseus. The quest also shows that Bob the Cat is the reincarnation of Robert the Strong.
In Dragon Slayer II you have to fight him while in Bob's mind.
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