Ankylosaurus was one of the most heavily armored dinosaurs that ever lived. Its back and sides were covered in thousands of bony plates called osteoderms, and even its eyelids were armored. The massive bony club at the tip of its tail was made of fused vertebrae and could swing hard enough to break bone — a powerful defense against predators like Tyrannosaurus rex, with which it shared its habitat about 66 million years ago.
Coloring ideas: color the armored bumps a cool grey-blue or dark olive green to give the impression of thick bone plates. Use a slightly lighter shade for the skin between the bumps. The large round club at the tail tip could be a darker brown or grey to show its dense, bone-like texture. Rocks and ferns look great in earthy browns and greens.
For younger kids, the large oval body shape is easy to fill in with a single color. Older kids can try shading each individual osteoderm with a highlight in the center and a shadow around the edge to make the armor look three-dimensional.
