You can get the lbx in the card battle, and the weapon, you can get it in the ranking battle or card battle (both of them in boost 5) And about the grind level, it’s in the name “grind”, so u gotta grind for that lol A faster way of grinding is to farm ranking battle rank 6 (that 5yrs old kid) My bad for not knowing the names of certain things cuz I play the Japanese version of the game