They finally get Battle Shock right.

Wow! I love the new Grotmas Chaos Knights army rule! Finally the mechanic we've been waiting for!!! Kinda weird that I'm forced to take 75% Chaos Space Marines allies though. 🫤 /s

https://www.warhammer-community.com/en-gb/articles/kdtvqqh5/grotmas-calendar-day-6-terrify-and-terminate-with-a-new-chaos-space-marines-detachment/