This is probably one of the most nerve-wracking parts to a video game I've played.
This a scene from Metroid Fusion, the second time you go to whatever sector TRO is. You go along an upper hallway and come to a gap where you can drop down. All you can hear are steady footsteps and the soft music that signals the SA-X is near. And, no matter what you do, you can't see it until you drop down in front of it, at which point it will try to kill you.
Seriously, though, the SA-X terrifies me. Bad enough that it's mimicking Samus at full power, with the goal of killing you, but Samus herself is much weaker than normal, what with large portions of her suit surgically removed and her Metroid DNA making her extremely vulnerable to cold.
Fun fact: This is my first time drawing the Fusion Suit. This is also my first time drawing Samus with a helmet on.
Metroid belongs to Nintendo. Artwork belongs to me.