These days arena is full fill of overpower class:

Berserker:
1-huge damage on super armor skill
2- can not be grab for two of superarmor skills
3- super fast movement speed

Yacha:
1- play nonstop superarmor skills, both superarmor skills have 2 times charges and long life cycle
2-can not be grab on superarmor skill with two times charge
3- long life time for grab skill

Kunoichi:
1- longest hidden time 6s
2- teleportable superarmor skill with long time target hold (about 4s)
3- her teleport ability could find other hidden class even on stealth mode
4- can not be grab on superarmor skill with two times charge
5- grab skill (combo grab after teleport skill)
6- hold on hidden mode even after attacking (not work target lock after attacking her on stealth mode)

Hope to clear and understanding by BDM that the game is not only for some few classes, this game has about 50 different classes and more than 10 Million download just on europe server.