General Note/Update (1) If you have Eren, Levi or Mikasa, you can get all the question mission in one run. They can single-handedly finish the EXs. (2) The "Clear without Mercenary" quest mission is negligible - it's just 5pcs Rainbow Ingot. Not worth the trouble if you don't have the squad to compete. (3) As for the 2 EX+, you need the AoT units (Levi/Eren/Mikasa) to effectively compete with those stages. The bosses there have tremendous HP that even Zahar will take years killing them. In other words, not for f2p players generally.