This whole sentence: "They will hunt you to the edge of the earth for this." Enough said.
Kruger. Practically Nightmare Fuel personified, it's a fairly safe bet that whenever he shows up in the scene, things are gonna get ugly real quick. Here's a few highlights:
Kruger, in his upgraded Exo-suit, walking down the hallway chasing Max, screaming about how he would find Max and how he would kill Max.
Kruger: You hear that sound?! That's the sound of me coming for you! I WILL FIND YOU! I WILL HUNT YOU DOWN!
His face getting blown off by a grenade. It's reconstructed, but not before we get a great look at Max's handiwork.
Kruger was born in 1970. He's been around ~200 years. Imagine all the suffering he's caused and would have caused.
Thinking through Kruger's plans after taking over Elysium can become high octane Fridge Horror.
Even without all of that, how Kruger kills Delacourt is terrifying to witness. It even get a little worse when taunts and mocks Delacourt after she's been stabbed. Then there's the music, which plays out more like an alarm than a piece of music.
During their final fight on the bridge, the way that Kruger's whole demeanor seems more like a kid horsing around with his friends than a man locked in lethal combat says a lot about his disturbed state of mind.
Kruger: Did I getcha? Are you bleeding? You should get that looked at, eh boykie!?
The Chem-Railgun. This weapon can essentially reduce anyone and anything in its path as it practically gives the middle finger to the law of physics and cover. If someone points this weapon at you, you will be reduced to swiss cheese within mere seconds.