Marcus's situation throughout season 2 is one of the most horrifying pieces of worries seen in the franchise. Someone puts out a public hit on his head before Purge Night, and although it fails, he's left with the horrifying paranoia that if he doesn't figure out who did it, he'll be in danger the next Purge as well.
Ben's entire character progression turns him from a relatively innocent if aggressive boy to a remorseless maniac who kills literally everyone he can possibly get his hands on, all within a single year. He is essentially the living embodiment of why the Purge would never work - it would only create more psychos like him.
The season does not shy away from showing just how much of a draconian state the United States would have to be under the NFFA's rule, with cameras absolutely everywhere and the NFFA killing anyone who could possibly pose a threat to them or the Purge. They even cover up violent crimes in order to make it seem like the Purge works.
Should I Stay or Should I Go
Kelen spends the entire episode essentially as a kidnapping victim desperately trying to escape from Ben's clutches, trying every strategy from leaving a note in a gas station to pretending to be okay with him being a Serial Killer. None of them appease him, and soon enough he tries to force her to cut him so she can feel the same rush he does, all while she implores him to realize that she doesn't want to understand what he's feeling because it's sick. She escapes by stabbing him in the leg, and while retreating she's hit by a car - and right when we think Ben might try to save her, he chokes her to death instead, scowling in rage all the while.
Before The Sirens
Marcus makes one of the most horrible decisions a parent would ever have to make - in order to keep his son safe, he has to hurt him. Because the only place safe from the NFFA is hospitals, Darren would need to be injured or ill in order to be safe, so Marcus breaks his arm with a wrench to ensure he'll survive the night.
Hail Mary
The Cold Open reveals that Ben's rage isn't anything new - as a child, when he learned that the Purge existed to help adults express their rage, he proceeded to smash his toy in vicious anger. It makes it clear that it's not the Purge making him this way, he was always ready to pop.
The entire scene in the triage center carries a horrific feeling of dread permeating it throughout. Not only are the scenes within it terrifying enough and showcase just how nightmarish the Purge would be, with people missing a startling amount of limbs, but we know that soon enough, Ben is going to wake up, and once he's up there will only be death.
