|| This article contains canon information corresponding to the Tales of Arcadia franchise. That means all information in this article is true and has appeared/been validated officially on-screen.
The Horngazels are the keys that open the entrance to Trollmarket. When used to draw an arch on the wall below the Arcadia bridge, a portal opens that allows one to enter or exit Trollmarket.
It is vital to not let a Horngazel slip into the hands of the enemy, or they could easily get into Trollmarket and attack, as Angor Rot did in Episode 26.
The Horngazel can also be used to block the portals it creates by simply creating an X over it.