Just like old times...
No, it wouldn't be "just like old times". In those days, Mamoru had been a disaster unless Kaoru or Keisuke were around. Even if, for some reason, Mamoru would be come incompetent in the middle of this mission, he'd no doubt be more useful than he had been as a genin.
He took Kimiko's words as a grain of salt; it was a little irritating that he would have to put in extra effort and incapacitate instead of killing (snapping a neck was actually a lot easier than knocking someone out because it worked every time) but he knew how to deal with it. As he took a communicator, he gave Kimiko a smile before switching it on. "Testing." Immediately after they were ready to go, he snapped into mission mode.
"I'll assume you're going to go barrelling through, Keisuke-kun?" He asked, his eyes set on their goal. "If you create a distraction, I can grab it and we'll be out of here in less than twenty minutes."
His friend seemed a little offset by the change in his demeanor, but quickly set pace with him. "Yeah, sure. Just don't get in my way, okay?" He gave Mamoru a smirk that the silverette was familiar with before he headed into the thick of their enemies.
I'll leave that to him. "I'll cover you, but I'm focusing on the prize." In the meantime...
With a sense of urgency, he began to toss his kunai on the ground as he snuck past guards, careful not to draw any attention to himself. After waiting for Keisuke to lure away the enemies (and hopefully incapacitate them as per Kimiko's instructions) he swiftly plucked one of the four artefacts from its pedestal. One~
The second one was not far from the last. Two~
The other ones must be in the next room... Another room...he pondered this for a moment. Might be traps...a few more guards...easy, I think.
Into his comm link, he said, "I'm going on to the second room. Two down."
He'd already tripped his own wires so that they would only react to foreign chakra; it would be impossible for Keisuke to set them off (though it was entirely possible to set them off without Mamoru being around), but he knew for sure that when someone did set them off, they'd end up "crucified".
It was a surprise worth waiting for, honestly.