Mages are powerful magic caster.
They manipulate mana, the energy that existed throughout all the world. It could not be seen but could only be felt by someone who is mana sensitive.
It gave them ability to manipulate elements, and even help improve one own bodies and accelerate or decelerate human regeneration properties among other types of improvement they could induce.
But everyone knows the weakness of a magic user is their physical body.
Other than some renowned combat magic user, most mages possess little strength of physical body.
There is a reason why those who clashed against Aero is warrior class or Paladins and why not many magic attacks were hurled towards Aero.
Aero when he began his attack would first ram himself to the mages in the group
With one ram charge towards them, these mages even while using reinforcement magic or Iron Body magic could not endure the impact of Aero ramming his body at them