Tiny bones joins up is a stronger version of hopeless nightmare but for the same mana when it comes to the first ability. However tinybones joins up has its second on a card that is only one mana cost and it is way to easy to build a deck around legendary permanents in this format. Hence it is a overpowered combo card. This is bad design like all accidental or intentional combos and should be banned. Wizards of the Coast needs starting actually playtesting their sets in

Rakdos joins up just punishes the opponent for destroying the opponent creatures. Giving the your opponent a penalty for playing the game is really bad design. This is more than enough reason to ban this card.