For those who still has trouble and those who had trouble in Test Server and are hesitant still or so. To really beat the Last Boss. You have to go back for first Healing Barrel and take it to the Last Boss and smash it on him,and fight, and survive a little, use cola, then survive a little. If your low on health, block until he attacks and falls, immediately then go back to the for the other corner healing barrel and smash it on him. Then survive, cola, and by then the Corner Barrel should be back. Do not bring both Healing Barrels near him. The other will disappear. So yes, you do have to travel back for the corner barrel. Sorry for the Grammar. Not good at it.
This mission is pretty straightforward, but the video is still worth a watch. For folks struggling, notice how the OP pulls off of the first mini-boss whenever the red tex "Alarm System Activated" appears and the yellow lightning bolt "destroy" icon come up over on the the terminals. Destroying the terminals before more adds join make this much easier.
