What is a Activision account for modern warfare?

Call of Duty: Modern Warfare 3 - Playstation 3 : Activision Inc: Video Games

Call of Duty®: Modern Warfare® II - Urban Veteran: Pro Pack - Call of Duty

Call of Duty: Modern Warfare Requires an Activision Account For Cross-Play

How to log into an Activision Account - PC Guide

Call of Duty Warzone 2.0 - How to See Your Activision ID

Modern Warfare 2 “Activision account could not be linked” error: How to fix, possible reasons, and more

How to add your friends to your Activision account in Call of Duty: Modern Warfare

My Activision account was hacked

mw3 account unban remove activision permanent ban now works for mw2 wa

Cant login to Activision account in-game, but can login on web browser. What to do? : r/ModernWarfareII

Call of Duty: Modern Warfare III - How to Get Started in the New Zombies Mode - Xbox Wire

How to Change Your Name in Call of Duty: Modern Warfare II