Rust Wolves were created by an evil wizard to enforce his evil rule. The wolves are 1.5 times bigger than normal wolves and have antennae. The antennae are used to spray a rusting agent onto metal to rust it. The wolves then eat the rusting metal to incorporate it into their bodies to make themselves stronger. This also weakens any resistance by disarming them of any metal. This idea was given to me by a friend on the Shield Hero Discord.