??? how did you possibly come to that? his other mythical beast could have had more attack previously, and they both gain 500 everytime a spell is activated. Also, he is not using Pegasus, so they're no way he could have the extra extra skill, so unless he had magical stone excavation he can't use it 4 times...
it's not a simple equation
Any options instead of this if you didn't pull it?
Well synchros are harder to summon and actually require some degree of skill unlike xyz which generally speaking only requires 2 or more monsters of the same level,not only that but most xyz monsters (even so called rank 4's) have pretty op effects,good example of a broken xyz is number s39 uptopia the lightning, synchros on the other hand have stats and effects that usally match their level.