Iggy is a orange and red Terrible Terror. He is the size of a typical Terrible Terror.
Iggy has a mellow behavior; when Fishlegs was about to name him he simply scratched his head and sniffed around. Iggy also seems to be irritated to Snotlout, as when Snotlout showed him a picture of a bucket, Iggy simply grabbed the bucket and threw it onto Snotlout's head.
Intelligence: Fishlegs trained Iggy to grab whatever the picture Fishlegs was holding showed. For example, when Fishlegs held up a picture of an apple, Iggy grabbed an apple with his mouth and gave it to Fishlegs.
Other names Fishlegs considered naming Iggy were Lars, Van, Slurg, and Deathwing.
Iggy is one of only two dragon to have human names. The other being Luna.