Perhaps he had some climbing experience or skills. If he was into rock climbing or mountaineering, he could have applied some of those techniques. He also might have had a lot of upper body strength, which would be crucial for pulling himself up floor by floor. Maybe he found some footholds or areas on the building's exterior that made it a bit easier for him to climb, although climbing 19 stories is still extremely difficult and dangerous.
He might have used the external structures of the building, like window ledges and drainpipes, to pull himself up.
If he was climbing for a legitimate reason, like a rescue operation or if he had prior permission from the building owner, then it could be legal. But just randomly climbing 15 stories of a building in Philadelphia without any authorization is likely against the law.
Maybe he was trying to escape from something, like a fire or a dangerous situation in the building. He might have thought climbing was the only way out.
It could be a dare or a part of some extreme fitness challenge he set for himself. Some people like to push their physical limits in unique ways, and climbing 15 stories is no easy feat. It might be his way of proving his strength and endurance to himself or others.
It could be that he is in an emergency situation. For example, there was a fire in the building and the stairs were blocked, so he had no choice but to climb the outside of the building. And he might have some basic climbing knowledge and enough courage to attempt this dangerous climb of 15 stories.
An adventurous person might do it. They love to take risks and seek challenges, and climbing 15 stories is definitely a huge challenge.
It depends on his fitness level. If he is very fit, it might take him around 10 - 15 minutes.
It could be that the elevators are out of order and he's in a hurry to get out of the building, so he chooses to climb down 15 stories. There might be an important meeting or appointment he doesn't want to be late for. Also, perhaps he just wants some adventure or a physical challenge, although climbing down 15 stories is quite a risky adventure. He might be a thrill - seeker who likes to do extreme things.
There could be several ways. He may have had help from others on the ground who provided him with something to climb on. Once at the second - story level, he would need to be very gentle and quick in getting the babies. If there were any obstacles, he had to overcome them. Maybe he found an open window or had to break a window carefully to reach the babies. After that, he made his way back down with the babies in his arms or in some kind of makeshift carrier.
Some slaves managed to tell their stories secretly. They might pass on their experiences orally within their communities. For example, through songs and folktales that carried hidden messages about their plight. Others, when they were able to write, like Frederick Douglass, wrote autobiographies that detailed their lives as slaves and their journey to freedom.
Well, he might use his agility and web - slinging skills. He could quickly move around, web up Venom to slow him down, and then lead him away from the Avengers.