How do you beat Robnos and Ruku in Zatch Bell Mamodo Fury?

PART1:this is probably the hardest part of the whole game, it took me FOREVER to beat him.

1:go to the very left(or right) of the room and you'll find a staircase

2:go half way up the staircase and switch to zatch

3:go up to the balcony and keep throwing zaker and zakerga attacks at him

4:make sure you lock on to him to destroy his body parts, you should go in this order when destroying his body(right arm, left arm, right leg).

youll will try it like 100 times before you can beat him

PART2:this is probably the easiest part of the game.

1:hit baltro(not with a spell)

2: he is now stunned for a few seconds, get away from him as fast as possible

3:lock on to him and right when he gets up launch a zaker at him

4:keep repeating the cycle until you get it right

CONGRADULATIONS!!!!!!! you've beat baltro, im pretty sure you fight maruss next