Yellow, red or dark blue
Cars Magazine N.23 comic 1
They appear in the Cars Magazine N.23 comic 1.
Since Mater-San beat Kabuto, their boss, this gang of ninja cars have being following Mater to take revenge! One day, they got to him and attempted to have a fight! But Mater told them he couldn't fight with them as his category was to high for them, so according with the warriors code, they should fight with Mater's best student: Lightning Dragon McQueen, so they could challenge Mater then.