If he's a goner, the least he can do is try and make it so Shura stays alive. Strange sends the fire towards Shura, snaking around her legs to try and destroy the one clawing her calves. That one vanishes, but as the fire leaves Strange, a few more of the imps get the jump on him, biting and clawing.

One of them succeeds at it's objective: Strange had already constantly been bleeding out from the side, but a large claw to the chest is enough to break his concentration. The fire, which had been circling around Shura, looking for another imp to destroy, suddenly snuffs itself out as Strange falls to the ground, bleeding profusely.

The shade imps take advantage of this and proceed to scratch and claw at Strange's body with reckless abandon, making sure that though he's down, he stays down. He is straight up dying at the moment.