trying to figure out what technique they used to paint the brick patterns on the wall. (would look good for the ''lego room'' we are planning)
too big to be a ''wrap'' or wallpaper , IMO.
maybe, black and white paint to base, and some kind of template for the ''bricks'' themselves ?
or ''tape and mask'' the whole thing 
The only alternative I can think of besides taping it off for painting is - get peel & stick wallpapers in black & gray & cut out the blocks from them & stick on the wall? Might be easier. With the peel & stick papers, tho, make sure the base paint on the wall has at least 4 weeks curing time first.
@VictoriaLandis1 @BLuOXide that was my first thought as well. Easy to get nice clean lines, and most 'Contact'-type paper has a cutting grid on the back. Have fun!
@VictoriaLandis1
good idea, cutting the block from peel and stick wall paper, 👍