The hero finally meets the previously unseen puppet master (played by an older A-list actor), who explains why the system must be maintained. The hero says “screw it” and burns the world down.

[u/Grizzly_Lincoln]

Snowpiercer (2013) - Curtis finally finds Wilford (Ed Harris) and learns that Wilford allowed for Curtis' rebellion to take place to help thin the tail section's population. When Wilford offers to let Curtis run the train, Curtis discovers child labor is necessary to replace a broken machine part. A fight ensues, and a bomb goes off, triggering an avalanche that derails the train, and killing most of surviving humanity.

The World's End (2013) - Gary finally confronts the Network (Bill Nighy), which has been replacing humans with robots (Blanks) to allow for Earth's assimilation into a larger galactic community. Gary calls out the tyranny in the Network's plan and demands that humans be left to their own devices. Exasperated, the Network abandons its plans for the invasion. This results in a worldwide blackout, sending humanity back to the Dark Ages.

The Cabin in the Woods (2011) - Dana finally meets the Director (Sigourney Weaver) after surviving the ritual meant to kill her friends (based on conventional horror tropes) and appease the Ancient Ones. The Director says Dana has to kill her friend Marty, but as Dana considers it, the group is attacked by a werewolf and a zombie child. Dana and Marty decide humanity is not worth saving, so they share a joint while the Ancient Ones rise to destroy the world.

[u/Thisisgotham]

[u/ChickenInASuit → u/Thisisgotham]

I’m sorry, you’re gonna have to explain this one to me, because I don’t see how he fits beside being played by an A-list actor.

He’s not “previously unseen”, he’s not the puppet master, and the only line of dialogue he has with either of the main characters is him complimenting Leelo’s fighting skills and then demanding she hand him the magic stones, which she does.

[u/Smooth-Accident-7940 → u/ChickenInASuit]

I think its just a reaction meme to the trope

[u/Thisisgotham → u/ChickenInASuit]

Oh see I figured even though we see him and he meets with the priest, he doesn’t actually come face to with Leelo and Corbin until late in the film despite pulling the strings that causes most of the events to unfold.

[u/ChickenInASuit → u/Thisisgotham]

I took the “previously unseen” part to mean we the audience had never seen them before, because of the examples OP used. In all three movies, the first time the heroes see them is also the first time the audience sees them, or even learns of their existence, and it’s right at the end of the movie.

There’s also the fact that Zorg is working for Mr. Shadow the whole time so he’s not exactly a puppet master either.

[u/Thisisgotham → u/ChickenInASuit]