"Agility training," Batman had said.

Robin hadn't anticipated that to mean he would end up being chased halfway around Gotham with nothing but his thirteen-year-old wits, a utility belt that was half-drained of supplies after two hours, and the adrenaline surging through his veins that made him all too aware of the hair standing at the back of his neck and the knowledge that somewhere behind him, maybe far but probably close, there was someone chasing him, and the moment he stopped to breathe or turn around that motion-blurred shadow would be upon him.

In shorter terms: Robin was not feeling the aster.

He wasn't sure what had ultimately led him to the Lower East District, but in retrospect, it was a good idea – the buildings were largely worn down and there were plenty of small gaps and spaces he could make shortcuts out of or, if worse came to worst and Bruce didn't mind footing the bill for property damage, create.

The ventilation shaft he was currently scurrying through had proven to be as such, with one unfortunate added bonus: it was also big enough for his shadow to fit through.

The echoing sounds were getting closer. Robin dug his climbing spikes into the side of the shaft and hauled himself up onto the ledge, then promptly began crawling down the length of the duct as quickly as he could. He turned a corner to be met by a ventilation panel and the humid stench of Gotham air filtering through the grate.

It was his ticket out. Robin twisted around as well as he could and slammed his heel into the grate, which came loose with a shuddering crack. He locked his fingers into the holes, pushed forward to detach the panel from its frame, and dragged himself out into the open air.

His feet landing soundlessly against the concrete, Robin felt his breath coming in pants as he spun around and placed the panel back onto the ventilation duct before jamming the sides with a handful of plastique. As with most of the buildings in the district the apartment complex was long abandoned, but he had no plans to detonate it. All it needed to do was convince his pursuer to take an alternate route that didn't involve crossing paths with explosives.

Plastique in place, Robin snapped the latch on his utility belt shut and turned on his heel, launching into a sprint across the rooftop and trying to ignore the angry bursts of pain with each footfall. His lungs were burning with the heavy scent of grime, and even his costume was beginning to chafe. Top priority was shaking this guy loose before he had to deal with the wedgie of a lifetime.

The sound of ripping metal clued Robin in to the fact that his pursuer had, in fact, found a new path in the form of tearing out of the duct itself; at the speed he was going, that put him at about a twenty-foot head start. Another spike of adrenaline pulsed through his body; he would not get caught. Not now.

He reached the edge of the rooftop and vaulted down into the fire escape hanging on the side of the next building over. Tight space, easy for him to maneuver, not so much for a grown adult. Climbing down the rails to the second story, Robin dove into a broken window whose space was already big enough for him to slip through. He swept his cape over his nose at the shower of dust kicked up at his landing and ran for the next room.

He made it to the doorway when the glass shattered behind him, announcing the entrance of his pursuer. Robin spun in a circle, foot hooking around a nearby chair's leg and dragging it in front of him before he finished the turn, and bolted down the hallway. He heard the sound of wood splintering as the chair was first coiled up by a weighted lasso and then immediately slammed out of the way by a heavy arm.

This apartment had been a poor choice. After years of abandonment, it was nothing but a few rooms of peeling wallpaper and spider-webs and moldy wood; Robin's footsteps felt soft and caused the floorboards to creak in agony. His frame was already light. With any luck, his tall, muscular assailant's feet would go straight through. With bad luck, half of the floor would go with him.

The thought was barely formed when he heard a crack and the ground dropped from underneath his feet. Robin felt his cape whip over his head as he fell backwards, tumbling down with a shower of dust and splinters hot on his heels. He landed on the backs of his shoulders and used the momentum to flip out of harm's way, ducking behind a washing machine while covering his face again.

The building seemed to shake for a few more seconds before settling down, and even then, the dust took several more. Robin leaned out from behind his cover to discover a pile of broken wood and plaster in the space he just occupied. He got to his feet, arm dropping slowly.

His pursuer was nowhere in sight.

Robin swallowed and took a shaky step forward, eyes growing wide. "Batman?"

A hand dropped onto his shoulder.

"Yes, Robin?"

Robin spun around to meet Batman's perfectly blank expression, his mouth dropping. The broken dots in his head suddenly drew together. "You...broke the floor on purpose."

"Interesting gamble with the plastique. I trust it will be removed before it causes any real damage." Bruce moved to the window and pulled a grapnel gun out of his belt. "I also trust that had I not been the one pursuing you, you would have kept moving once the floor fell through."

"Oh." Robin scratched the back of his neck. "Does this mean I fail?"

"No. Two hours is an improvement over your last time." He looked back at Robin. "Next week, I will be evading you. In other words..." The grapnel shot out of the window, and Dick had just enough time to see the smile on his mentor's face before he turned around. "You're it."

Batman's cape fluttered as he left, and Robin ran to join him, laughing. "Aster."