Zhang's drawings emphasize their bulging eyes, flared nostrils and pricked ears.

Take the acclaimed Houmuwu Ding. The square cooking vessel is considered the world's heaviest piece of ancient bronze discovered. It's housed at the National Museum of China in Beijing.

"Monster masks" adorn its top and bottom.

Zhang illustrates the masks as two kui dragons in the same shape but with different motifs.

He also depicts its two handles decorated with two tigers facing each other. Their jaws close around a human head, seeming to aim at intimidating the civilian population and conveying the emperor's authority.

The upper part of the caldron's four feet is also adorned with monster masks above three-cord designs in Zhang's illustration.

During his self-quarantine, he reposted his drawing of the pair of bronze lions that guard the Gate of Supreme Harmony (Taihemen) at the Palace Museum in Beijing.

In his illustration, the "angry" mother lion is holding a cub in her paw. The cub says, "I want to go out". It makes people laugh.

Many netizens describe his cartoons as their first "clear picture of bronze ware".