AttackER, only one, that attacker was preoccupied with another fight with someone who was more than evidently capable of dealing with him on his own. And since Sukoh couldn't do a DAMN thing to him while he was in the building he went off to do his own thing. 

Alertness only goes so far.

Don't forget.

Near 3x the speed of sound. He literally could not hear you coming, the slight inkling on the back of his neck was the only way he had any sort of sense of the two approaching.

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