- "He looks like my brother-in-law! I should probably kill him, too."
- — Nikolai Belinski
Shrieker Zombies, referred to as Sonic Zombies in the in-game files, are a variant of zombie appearing in the Zombies map Shangri-La. They have a whitish-blue glow to their appearance along with pale white skin, and blind the players temporarily by shrieking at them. They appear throughout the normal rounds as they do not have a dedicated round. They do not count as part of a round, so the round may change even if they are still alive. They spawn by blasting their way out of the ground with a sonic screech, so chances are the player will hear a Shrieker before seeing them. They also sprint constantly at a high rate of speed similar to that of the sprinting zombies in Verrückt, Call of the Dead, and Moon.
- Small Consolation (10 / Bronze Trophy ) - Shrink every zombie type with the 31-79 JGb215.
- Blinded By the Fright (30 / Bronze Trophy ) - In "Shangri-La", kill a Shrieker zombie while blinded by it.
- If the player shoots a Shrieker in the head, all zombies' heads near it will explode.
- The Shrieker Zombie is affected by Insta-Kill and Nuke.
- The Shrieker Zombie can spawn in as soon as Round 4.
- Shrieker Zombies, along with Zombie Monkeys, are unaffected by the fire patch created when a Napalm Zombie dies.