Fortunately for Tai, Robert seemed to do a good job of freeing himself from Edgar's grasp, even if the bull Grimm was still intent on murdering him. This was apparent by the way Edgar ran into a boulder, smashing his horns and at the same time sending Robert to the ground, though Tai couldn't help but notice that he happened to have a card now. And then the Grimm's horns managed to regrow in a matter of seconds, impressive at that. 

Fortunately, Priscilla intervened to make sure Robert didn't die a gory death as Tai rushed forward, apparently phasing through the Grimm somehow, which was a useful Semblance at that. Suddenly there were shouted directions, and Tai shifted wordlessly to accommodate the instructions, his meteor hammers whipping about in rapid motion, chains wrapping around and crushing limbs, when a hammer strike didn't land on the smaller Grimm that surrounded them.

His actions were careful, controlled. To do otherwise was to risk his weapon flying out of control and doing things he didn't want them to do. Overhead leaps and smashes with raised ball and chains, powerful thrusts where he tossed one head forward and then yanked it back, the meteor hammer was a classic weapon that was a testament to the skill of the user in controlling it. And he used it now as he took down Grimm after Grimm, saving the fire dust laid upon it for when it was truly needed.