Ironhammer the Giant is a character version of the card, "Ironhammer the Giant", which is part of the main cast of The Sparrow's TV show.
Although Ironhammer the Giant was never shown as a character, Nelson, who plays the role of The Sparrow, uses the card version of it on his Deck, which is entirely based on the TV show. The cards hint that when Ironhammer the Giant, The Sparrow, Phoenix Beast Gairuda and Beast-Warrior Puma unite, they can control a giant spaceship.
Astral, who watches the show, explains to Yuma that Ironhammer the Giant was once almost discarded for having a defect, and that he is the iron knight who was saved by The Sparrow. He is also revealed to have a great sense of protection towards The Sparrow and to be a bit naive.
Yu-Gi-Oh! D Team ZEXAL
Ironhammer the Giant makes a brief appearance in Yu-Gi-Oh! D Team ZEXAL, as one of The Sparrow's allies in the TV show.