competition: Most confusing RIDDLE

There are three omniscient gods sitting in a chamber: GibberKnight, GibberKnave, and GibberKnexus, the gods of the knights, knaves, and knexuses of Gibberland. Knights always answer the truth, knaves always lie, and knexuses always answer the xor of what the knight and knave would answer.

Unfortunately, the language spoken in Gibberland is so unintelligible that not only do you not know which words correspond to 'yes' and 'no', but you don't even know what the two words that represent them are! All you know is that there is only one word for each.

With three questions, determine which god is which.