It's behind their group, not in front, so there's little he can do to take the brunt of the blow from that fist. He does spot the mage rather quickly, however, and it's her he takes a running charge at. If he can disrupt her spell long enough, the others may have a decent shot at her.

He's got a feeling running right up to her might trigger some kind of trap, but better he take it now than let her continue to take pot shots at them from long range. They're supposed to be making noise, after all.