After 14 seasons of Supernatural, it's impossible to believe that there are still topics the series has not touched upon. The long-running CW series, which air its 300th episode on Thursday, has featured musicals, time travel, alternate universes, the apocalypse, an animated Scooby-Doo crossover episode, getting sucked into a video game, a sitcom parody, a Looney Tunes gag, and a time loop. Supernatural has seemingly done it all. And yet, that's not quite true.

We might have to stretch a bit, but there are a few frontiers that Sam (Jared Padalecki) and Dean (Jensen Ackles) and the gang have not yet explored. So as the show approaches its landmark 300th episode, here is what we want to see the show tackle before this road trip from (and to) hell wraps up, whenever that maybe (the show was just renewed for Season 15).

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Jensen Ackles, Jared Padalecki, Samantha Smith and Jeffrey Dean Morgan, <em>Supernatural</em>Jensen Ackles, Jared Padalecki, Samantha Smith and Jeffrey Dean Morgan, Supernatural

Aliens

No, like, real aliens. Maybe Chuck (Rob Benedict) has some humanity prototypes floating out there in the Andromeda Galaxy that he'd rather forget happened? Maybe Chuck isn't the only omnipotent creator of worlds out there? Is there a Supernatural universe equivalent of the Men in Black? Dean could barely handle an airplane. Let's stick him in a spaceship. For science. And lulz.

Dean Winchester in the Study with the Colt

Admit it: a kooky whodunit caper in a haunted house would be hilarious. Maybe it is the result of some sort of screwy demon game? I don't know. But I do know the world needs more Clue parodies.

Vamps, Tramps, and Keystone Cops

I know silent films are inherently creepy. I also know it's because of film speed and stuff getting distorted when converted to other media and science that people way smarter than me can probably explain in more graceful terms. Still, remember how good that Nosferatu episode of Are You Afraid of the Dark was? I know we have Season 4's "Monster Movie" to satiate that classic Hollywood monster hunger, but I'm not talking about a regular episode that happens to involve silent film monsters. I'm talking about a complete silent film parody in the vein of "Ghostfacers" or "Scoobynatural." I know it would be weird. It would be extreme. It would be risky. Supernatural excels at weird, extreme, and risky though.

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Jared Padalecki and Jensen Ackles, SupernaturalJared Padalecki and Jensen Ackles, Supernatural

Put the Lime in the Coconut

I understand the reason we never see Sam and Dean in their swimmies in Key West is because Vancouver can only fake so many different climates and the tropics definitely isn't one of them. Doesn't the show feel kind of incomplete, though? Isn't it odd that for all of the coast-to-coast travel, all the drives up and down every coast and around and back again that apparently the beach is never haunted? The ghost of Annette Funicello would like to have a word with Dean and Sam Winchester.

Supernatural Abroad

Yes, I know the brothers Winchester technically traveled to Scotland in Season 6's "Weekend at Bobby's," but that hardly counts. For one thing, we didn't get to see Dean white-knuckling it through an international flight. For another, we never actually got to see the boys in action overseas. Show it, Supernatural, don't tell! There are rich stories and legends to draw on that the show is missing out on. The Enfield Poltergeist? The Tanzanian Popobawa? It's a big, spooky world out there.

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Let's Get Regional

Even if the series can't bring itself to subject Dean to the horrors of modern flight, there are some myths and legends here in the States that, somehow, 300 episodes later, Supernatural hasn't touched. I'm talking, of course, about West Virginia's infamous Mothman (which could be an alien, you guys!) and the Jersey Devil of the New Jersey Pine Barrens. There's also Pittsburgh's Charlie No-Face and the Villisca Ax Murder House in Iowa. How has this show been on the air for 14 seasons and somehow not paid a visit to the Winchester Mystery House in California? How?

Supernatural airs Thursdays at 8/7c on The CW.

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