Happy didn't know what the hell was going on but he knew he had to get the fuck out. The building started to vibrate and he ignored it because it was weird but he was pretty used to weird things. Somehow he'd found himself in the Avenger's gym with Alex, teaching the kid to box. He only offered the kid a bemused smile in answer to any unspoken question about the shaking. Maybe Tony was remotely running something in his garage or something. When the alarms started blaring, though, Happy finally took notice and headed for the door. There were different alarms for different crisis. The one that JARVIS was blaring now was a weird combination of the attack and earthquake alarms. Happy didn't know what that meant but he realized it wasn't good.
He stopped suddenly and glanced down at Alex, unsure suddenly of what to do. He knew they ought to get down before the building came down (which was clearly happening, the shaking had grown worse) but his wife and baby were still up in the penthouse as far as he knew and he wasn't going to leave without them. He didn't want to leave Alex alone, though, either. "Look, kid, can you make it downstairs alone? I need to go up and find my wife-" He looked around as another warning blare joined the cacophony. It was the one that meant the undead had breached the tower's defenses.