(As commonly used on the show Grey's Anatomy)
Derek: Oh... I usually just say "Meredith" and then you yell at me. I haven’t thought past that point. I actually didn’t have anything planned. Meredith hits him repeatedly with her purse
Derek: Listen! Hey stop it! Ow!
Meredith: Seriously? Seriously?!
It never unlocks exactly on 10000, the player is mostly required to get around 13-15k kills.
The achievement can also be unlocked by glitching it, by using another account that has seriously.
2nd Person: Haha, I can just glitch it.