He was voiced by Gideon Emery.
Anthony first appeared in "The Return of Strongbow" where, eight years in the past before the series when Eugene was still a criminal when during a robbery of a royal caravan, Weasel betrays Flynn and Lance and then he makes off with the goods, Weasel notes that his actions were "Baron's orders".
He is also seen during the end of the episode at the Baron's vault after Eugene and Lance try to steal from it but he isn't seen for long.
Weasel returned in "Big Brothers of Corona" he was sent by the Baron to capture Angry and Red for double-crossing him. but when they had just captured them and where about to take them away Eugene offers him a deal where Anthony frees Angry and Red in exchange for Eugene and Lance, Weasel decides to let them go commenting on how that was an unusually heroic deed, he lets them go and send his henchmen to get Eugene and Lance. but after deciding to come and help them Angry and Red are able to fend off the goons and free Eugene and Lance, sending Weasel away in the carriage.
In "Beyond the Corona Walls", Weasel appeases informing the Baron that Flynn Rider has returned to Vardaros, where he has established as his base of operations. Weasel and the Baron's other goons go and kidnap Rider and Strongbow to have Eugene marry the Baron's daughter, Stalyan. the plan was going well until Rapunzel crashes the wedding. During the final battle, the Baron is bitten by his own spider, since the veil to cure him was already used up it forces him and Stalyan to leave the city in search of the cure.
In "The Return of Quaid", the Weasel and his goons decide to take over Vardaros in the Baron's place after he was run out of town, but his takeover of power is challenged by Rapunzel. They are unable to defeat the princess on there own, so Weasel vows to return stronger, so he hires a bounty hunter named the Collector to get rid of her. Unfortunately for the Weasel, Rapunzel gets the help of the retired Captain Quaid, and they manage to defeat the Collector and Weasel forcing him to retreat finally freeing Vardaros.
In "Max and Eugene in Peril on the High Seas", he alongside the Stabbington Brothers, Lady Caine her horse Axel, and Dale take took control of the ship and planned to take off at the mainland, only to be thwarted by Eugene, Max, Rapunzel, and the rest of the gang.
In "Plus Est En Vous", he alongside the Stabbington Brothers, Lady Caine, Dale, Andrew, and the rest of the villains appear at the end of Plus Est En Vous. It is also revealed that an unnamed lady (who is presumably his mother or his wife) is hugging him.
Weasel can best be described as a sadistic, power-hungry and greedy person, who is willing to do absolutely anything to achieve his goals including murder, and hiring a bounty hunter to kill the heroes and is shown the enjoy what he does and take pleasure in the suffering of others.
He could possibly be considered one of the evilest characters and even worse than his boss while the Baron has some honorable traits Weasel has none and has done far worse things than the Baron. And the Baron genuinely cares about his daughter while Weasel only cares about himself.
Weasel is also shown to be a coward when left defenseless as when his men were defeated in "The Return of Quaid" he immediately ran away.