I hope you don’t cry easily, because this one’s a tear-jerker. If you looked really closely during a certain scene in Drew Goddard’s The Cabin In The Woods, you might’ve noticed a few unexpected cameos. Without spoiling anything, though seriously, if you haven’t seen this brilliant film yet, you need to remedy that immediately — the Witch, Boomer, and Tank from Valve’s Left 4 Dead series can be seen doing their thing in a scene near the end of the movie. I noticed the Boomer when I saw it in the theater, but I didn’t notice the other two, or Alma from F.E.A.R., until I watched it at home where I could pause it every half-second to more easily soak in that fantastic final act.

Apparently, there’s a reason behind this. During a recent Reddit AMA, Goddard explained the reason behind the appearance of these characters. It’s a little spoilery, so head past the break for more.

“We actually were going to do a downloadable L4D2 expansion pack, where you’d fight in the Cabin world, but then MGM went bankrupt so the delay squashed it,” Goddard writes. “But the people at Valve were still cool enough to let us use some of their monsters to fill the cubes in the background (I had a lot of cubes to fill).” said Goddard, who’s referring to the massive, underground room filled with caged up monsters the facility unleashes upon the unsuspecting teens.

“By the way – the game was gonna be amazing. You were gonna be able to play in both the upstairs Cabin in the Woods world and the downstairs “facility” world with all the monsters. Believe me, I HATE all video games based on movies, they always suck, but porting Cabin into Left For Dead felt like the right fit. It pains me that it didn’t happen.”

Yeah, me too.

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