Abe's Oddysee and Abe's Exoddus were the best games for me from Oddworld Inhabitants (Surprise: I haven't played Munch's Oddysee or Strangers Wrath and I haven't seen pictures from the gameplay.
)
Back to the thread: Mudokons. Without them no Abe's Oddysee, Abe's Exoddus or Munch's Oddysee would have been released.
Of course that isn't the only case I like them.