I am surprised this card has still not been reviewed. Jubayr is quite easily one of the best defensive allies of the game, with the right stats and abilities. It's worth noting that its shadow card discard is not necessarily to be used against the enemy it's defending against so you could send Jubayr the defend against a small 3 enemy and use its ability to discard a shadow card from a non-unique 6 (or more) enemy against which sending your Felloswhip uberdefender. Jubayr can also be beefed up with cards like Raiment of War, Squire's Helm or Hauberk of Mail.