Dean isn't exactly a fan of Sam telling him what to do — it's one thing to have Sam watch his back. It's another entirely to have Sam tell him to sit tight. The only reason he listens and doesn't get out of the car is because someone needs to keep lookout, and the way his reunion with Sam has been going, if Dean follows, all they're going to get out of this situation is argument.

So fine, he sits back, takes out his pistol, scans the area, and let's Sam do his thing. It sounds like he handles a Croat out there, and if there's one, there is probably more, so Dean is ready to take out any that appear.

Except, no other Croats appear. A car does instead, headlights catching Dean's eyes and reminding him that he has a headache. End of the world, and he still has to deal with some asshole leaving his brights on.

As Sam returns, Dean gets out of the car and goes to step beside him.

"Lemme handle this, Sam," Dean says, warning in his tone. "My way."