User blog comment:Thailog/Ep. 203 "Alienated" discussion/@comment-76.220.44.198-20120512183153/@comment-4928331-20120512234305

Aqualad was occupied with the battle. Why would he plant a bomb downstairs, hurry back upstairs, and then try to retreat downstairs?

In any case it's not him nor a random manta man. There would be no need to hide that figure in shadow in that case. Maybe a (not THE) Blue Beetle?