When Adam climbed out of the cage, he had one thing on his mind - revenge against the brothers who had left him in Hell. He had been stuck down there with Michael and Lucifer for centuries and nobody had come to save him. They'd pay for that in a multitude of ways, he'd make sure of it.
Unfortunately, the hard part was locating them - the Winchesters and their angel(s) had gone underground since Chuck unleashed yet another apocalypse. However, he wasn't about to let that stop him.
He couldn't stop laughing when the locator spell pointed him right in their direction - Sam and Dean hadn't accounted for the fact that someone related to them by blood could be out there.
Adam wondered if he should torment them from a distance at first just to fuck with them, see how they'd react, but eventually decided against it - he wanted the element of surprise. It'd work out in his favor if they didn't see him coming.
Adam waited until they finished salting and burning a ghost to make his long awaited entrance. "Hey!" he called.
Sam and Dean's heads snapped up in shock and he smirked as his eyes went black.