Krogan

Krogan is one of the two main antagonists in the Netflix computer animated TV Series, Dragons: Race to the Edge and is the second-in-command of Drago Bludvist's army. He serves as the tertiary antagonist of the episode, Last Dragon Auction and the secondary antagonist of the episode, Midnight Scrum. He is one of the two main antagonists of the 2 last seasons alongside Viggo.

Biography
Krogan first appeared in the episode "Last Auction Heroes",  where he participates in Viggo's Dragon Auction as a special guest. When Viggo starts selling Hiccup's Night Fury, Toothless, Krogan soon takes an interest and wins the bidding. However, he takes back his money and flees without the Night Fury when Berk's Dragon Riders caused a panic by freeing the auction's dragons.

Krogan reappears in the episode "Midnight Scrum", seeking the bounty placed on Hiccup's head by Viggo Grimborn. He knocks out Throk with a dart after a difficult fight and captures Hiccup. But upon bringing Hiccup to Ryker Grimborn on an island, he is betrayed and ambushed by several Dragon Hunters, whom he manages to defeat. Later, Krogan attacks Hiccup, who had escaped during the ambush, stating that he would take him to Viggo himself to get the bounty. During their fight, Hiccup removes his mask and recognizes him as the same man who attempted to buy Toothless at Viggo's Dragon Auction, much to Hiccup's anger. Eventually, they both end up hanging at the end of a cliff, Krogan grabs onto Hiccup's prosthetic leg and tells Hiccup to drag him up. However, much to his shock, Hiccup, still angry at him for attempting to buy Toothless, instead removes his prosthetic leg and sends Krogan falling below to his apparent death.

After the Stoick the Vast and the Dragon Riders rescue Hiccup, Ryker attempts to kill the latter by throwing a dagger at him, only for Krogan, who is revealed to have survived his fall, to knock him out with Hiccup's removed prosthetic leg. But realizing that he is outnumbered by the Dragon Riders, Krogan jumps from the edge of the cliff and escapes without a trace.

Sometime later, Krogan forms a partnership with Viggo to lead the Dragon Hunters. He soon gathers his best warriors to form a group of Dragon Riders called "Dragon Flyers". They ride Dragons know as "Singetails".

Viggo then returns to the Volcano on Dragon's Edge to find the Dragon Eye. Krogan has his doubts though about the Dragon Eye still being in tact. Viggo soon finds the Dragon Eye and tries to fix it in Hiccups inn.

In the shadows, Krogan prepares to kill Viggo but was stop when the Dragon Riders came to take back their home. They are soon driven off Dragon's Edge with the Dragon Eye in their hands.

Krogan and Viggo soon meet up with Trader Johan (who has been revealed to be a spy for the Dragon Hunters) to check a rare Dragon Eye lens that leads to the "King of Dragons".

Personality
Krogan is very quiet, and seems to prefer observing from afar. Most of his actions are unpredictable and overly dramatized. Although an antagonist, he has a sense of honor.

Krogan has shown to be very ruthless, cunning, and sadistic, much like his boss Drago. Like Drago, Krogan sees Dragons as nothing more then living weapons of mass destruction.

Physical Appearance
Much like his boss Drago, Krogan wears a cloak made of Dragon skin. Under the cloak, he's a rather thin man, but has a muscular upper body. He has black hair, olive toned skin, and a goatee.

Abilities, Skills and Talents
Combat: Krogan is a highly skilled combatant, able to use his axe and fists to fight and defeat the Defenders of the Wing's second-in-command, Throk, and multiple Dragon Hunters. He also uses a long chain to capture and restrain Hiccup.

Agility: Krogan can leap high to attack and can evade enemies attack.

Stealth: Using his dark cloak, he can be very stealthy.

Controlling Dragons: Like his boss Drago, Krogan can enslave Dragons to his will. He uses this skill to enslave Singetail Dragons to do his bedding. He rides them like other Dragon riders. 

Trivia

 * Due to Krogan being Drago Bludvist's second-in-command, it's possible that he will appear as the secondary antagonist in How to Train Your Dragon 3, as it's very likely that Drago will return.