The Grabber can hold little monsters.
Flaming Zombie in Delta Labs.
There are survivors in the Erebus Complex.
The artifact can be charged with human souls.
The level design is amazing, especially in the first part of the game.
The first boss. Kill him to get slow time ability.
Vulgars always shows up in the green portal.
Travelling inside the SkyTram.
Activating the teleporter.
The second boss. Kill him to get Berserk ability.