With both customers and store employees dressing up as the film's Na'vi characters, turning the release day of Avatar into an event, the film's DVD and Blu-ray discs become 2010's biggest seller in just four days in North America.
On the first day it broke sales records, with the action-adventure moving 1.5 million Blu-ray copies on April 22, Earth Day in the US, to coincide with its environmental theme.
The 2D version of the sci-fi epic has sold 6.7 million copies of the DVDs and Blu-ray discs, echoing the feature film's biggest-ever box-office record.
Previously, the top seller for DVD and Blu-ray was The Twilight Saga: New Moon, which has sold 6.5 million units since March this year.
The home entertainment division of 20th Century Fox Home Entertainment told entertainment news website Deadline Hollywood, that Avatar 2D is now the No. 1 launch on both formats in the US, France, and Germany. It releases in the UK on April 26.
A special edition of this James Cameron blockbuster, including bonus features, will release later this year. The 3D Blu-ray version comes out early in 2011.