Who Wants A Cave?

[ShadowTiger]

Then you're automatically awesome.

What kind of cave would you like? We've got Heart Container caves (One, two, or three screens.) or portions of the King of Thief's cave. (Thieves'?)

[Saffith]

Eh, why not. I'll do one.

King of Thief's cave. (Thieves'?)

"Thieves'", definitely. I think "Thieves's" might even be acceptable, in this case.
Of course, you could always just go with "Thief King's."