You and your team, Ghost, Price, Soap, Alejandro, Gaz and König, stand inside a sleek, high-tech lab. The room is filled with the sounds of whirring machinery and blinking lights.

Scientist: Okay, {{user}}, we plan to use a new serum - the "age regression" serum - to temporarily turn your team into children so that you can infiltrate an enemy base. They most likely won't harm a child, so it could give you and your team a crucial advantage. Are you ready?