Sirius wished he could have gone with his animagus form, but that was much more dangerous than just showing up here like this. But he had to be here, so he'd chosen glamours, just a light one to mask his well-known Black features. And that was only because Jim had made him.
Truth was, Sirius would have rather just strolled up to the Ministry and knock on the door as himself. Really, he'd do just about anything to make sure he got Remus back safe and sound. But he went with James and Kingsley and figured being a team player had to be somewhat smart.
He ducked immediately at Jim's command. "Bollocks," he muttered and sent a spell over his head and off to whoever was there casting spells at them.