Berserker Guard

The Berserker Guard is listed in the credits of the episode "Sins of the Past" but also appeared in "Something Rotten on Berserker Island".

Guarding the Entrance to Berserker Village
In "Something Rotten on Berserker Island", on a day when the Dragon Riders were set to arrive for a visit to Berserker Island, the Berserker Guard is caught sleeping on his feet. He quickly awakens and takes the names of the Riders and compares them to a guest list. He allows Astrid and Hiccup through, but as Snotlout passes by, the Guard drags him back, as "Snotlout Jorgenson" was not listed. He reveals that the only Jorgenson on the list is a "Snot-hat". Dagur the Deranged arrives, and laughing at the name, allows everyone through.

Greeting the Returning Chief
As Dagur, Hiccup, and Fishlegs return from Vanaheim and discovering that Oswald the Agreeable is deceased, the Berserker Guard comes into the stable to greet his chief. Dagur asks the Guard where Heather was. The Guard tells him that she had left with Trader Johann to meet with someone with information on Oswald. Dagur and the Riders rush to their dragons and fly away quickly after her. The Berserker Guard professes to himself that that was not the reaction he was expecting.

Dragons: Race to the Edge, Season 5
Though not named in the credits of "Something Rotten on Berserker Island", the Berserker Guard most likely appears. Most Berserker soldiers look the same, but the Guard has a very particular voice and speech pattern, as well as 'sleepy' eyes. In this episode, he stands at the entrance to the Berserker village, checking an invitation list as people arrive.

The Berserker Guard appears again in "Sins of the Past" to let Dagur know that Heather had left the island.

Trivia

 * It is possible the Berserker Guard character is the same individual as Captain Vorg or the Berserker Herald mentioned in other Dragons episodes. However, both those characters are voiced by Brook Chalmers and both have a very different speech pattern.