Well. Thanks to the info dump that Rita gave him, Strange knows what he has to do now. Seeing the Mother puppet Rita like this makes him feel a little sick...and the fact that he might have to hurt Rita makes him feel even sicker.

Them's the breaks, he supposes. You do a lot of things you don't want to in war.

"Restrain Yukio!" he calls out, hoping Rin or Shura hear him. "She can go back into him!" As he does so, Strange thrusts out a hand pointed in Rita's direction. A gust of wind shoots out from his hand, aiming at the back of Rita's knees. If that doesn't knock her over, it's at least powerful enough to be noticeable.