I think that for comedic relief, the black knight should be able to be bypassed in conversation if one can quote Monty Python's Holy Grail bridge scene:

What is your favorite color?

Alternately, the introduction of the bridgekeeper might be amusing.

Vorpal Bunnies....

The legendary black beast of aaaaaaaaaaaaarg....

Heh that might be fun.

Oh, but I wish they had a bunny model in the game. I wanted to do the bunny thing a long time ago 8(

Badger...

I'll play with the toolset and see what I can cook up.

I would really like if its a random, low incidence encounter that has the odds of an interesting drop.

Does the Gank Beast still make occasional appearances? ...that's (a little bit) like The Legendary Black Beast of Aaaaarrrrrrggghhh
Has anyone killed it? ...did it drop anything?

I have killed him and he didn't drop anything

Ive killed it 3 times with different characters, not a single drop.