You name it, Sam and Dean Winchester have done it. (Unless, of course, you’re talking about normal activities like buying their first homes, starting 401Ks, or owning credit cards with their real names on them.) But in the supernatural realm, it’s hard to find a monster they haven’t heard of, killed, or befriended.

Over the course of 241 episodes, The Winchester brothers have been to Hell and back, killed Death himself, come face-to-face with God, and prevented the apocalypse… and they’re not done yet. Heading into its 12th season, Supernatural is already the longest running show in CW and WB history, and according to CW president Mark Pedowitz, as long as Padalecki and Ackles are happy and the ratings are relatively stable, Supernatural has a long life ahead.

But the key to living such a long life — besides coming back from the dead, of course — is never looking too far down the line. For Ackles and Padalecki, their focus is on the next milestone: hitting 300 episodes. “In a marathon, I keep my sights on that next mile, wherever that might be,” Ackles says. “And 300’s a good number to work for.”

Episode 300 would take the show 13 episodes into season 14, or all the way through season 14 if they did a shortened season, something Ackles and executive producer Bob Singer have talked about as a potential option. “We talked about wanting to be able to know when our end was, and if it was to be, let’s say, 300 episodes, we could tell a 13-episode story,” Singer says. “I think it would be bad for this show to just ride off in the sunset without a finale. I think we’ve earned that. I don’t know what that finale is, but we’d certainly like to do one.”

However, Ackles and Padalecki don’t want to get too ahead of themselves. If Sam and Dean have taught them anything, it’s that Death can be lurking around every corner (and he’s usually eating pizza). “If we don’t make it to 300, I think Ackles and I will both be truly bummed,” Padalecki says. “When we get to 300, I think Ackles and I will think it might be time to say bye. There’s a chance that changes, but we certainly do not take it for granted that we’re going to make it to 300.”

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At this moment, all they know is that they still love these characters. “I feel I’ve learned a lot from my friend Sam. I’ve learned a lot from my friend Dean. I want to tell that story as well as possible as long as possible, but I don’t want it to get too long in the tooth,” Padalecki says.

Ackles chimes in: “I feel like if I ever show up to set and I feel like I don’t care, or if I feel like he doesn’t care, then that’s the canary leaving the mine. To this day, I have not really ever sensed that from myself or him… They’re paying us to bring that little bit of magic to what they wrote, and I still feel that magic today. The day that I don’t feel that magic will be a very sad day, and I hope that day never comes. I’d like to get to 300 before that day comes.”

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For now, there’s still plenty of gas left in the Impala’s tanks. Speaking of which, the only thing that’s certain about Supernatural’s end is Baby’s fate. “He gets Baby,” Padalecki says of Ackles. “I get Baby Two.”