YMMV / Half Life Lambda Core

• Goddamn Bats: The Alien Controllers fly and shoot at you and the scientist trying to open the portal to Xen. If the scientist dies, it's even a Non-Standard Game Over.
• Paranoia Fuel: Vortigaunts and grunts appear out in nowhere much more frequently and erratically to the point of possibly causing a Jump Scare. It's the kind of level designed to sharpen the player into being trigger happy, anticipating combat any second.