Terrifying sights and sounds of Halo 5's MP?

What do you think are the most terrifying sights or sounds that can be experienced in Halo 5’s multiplayer?

Here’s my personal selections:

Sights:
A barrage of grenades from a Plasma Caster bouncing towards you.
A vehicle about to ram you when your evade hasn’t recharged.
A enemy banshee divebombing towards you.
Coming face to face with a sprinting enemy spartan as you round a corner.
A huge mass of infected pounding towards you when you are the last man standing.
An atrociously bad K/D being displayed for all to see on the post-game carnage report.

Sounds:
Hearing a Ground Pound charge right above your head.
The sound of your vehicle being hit by an EMP.
The sound of a sniper bullet zipping past your head.
The tick-tick of grenades being flung into the armoury you are currently occupying.

The sound of a phaeton in the air.

Sights: On Escape from A.R.C, a team of achilles spartans charging your armory.
A spartan spartan charging at you.
A sword lunging at you, especially in infection.
Scope glint from snipers.
An extremely good player completely out strafing you.

Sounds: The trusters of a spartan behind you, then the bang of him spartan charging you.
Any death noise you make.
“Enemy team scoring” in Strongholds.
“Bmmmmm” “Enemy captured the (whatever base just got captured).”
“Game over, DEFEAT.”
“We can still destroy the enemy core” :(.

All of your teammate’s waypoints turning into red Xs at once.

Sights:
-Walking right into a guy with a sword.
-Zooming out of a Sniper, looking at your radar, and seeing a red dot right behind you and then suddenly being moved to third person…

Sounds:
-“Enemy team has eliminated [insert boss name here]”.
-Various noises from kids with poor mic etiquette.