Ivar is much bigger then Jack in this devil cat form and he uses that to keep the man pinned. He's aiming to rip out Jack's throat to end this when he sees Jack's arm coming up to hit him, so he turns away from Jack's throat and chomps down on his arm.

There's a new spasm of pain as the volts of electricity hit him, shocking him once again. He's growing very weary of this trick. <Stop that!> He says, finally speaking during the combat.