WARNING: The following contains spoilers for Season 1 of The Idhun Chronicles, available on Netflix.
In Netflix's The Idhun Chronicles, while a lot of the tutelage of the young mages, Jack and Victoria, falls on the shoulders of Shail, many other lessons are offered by his partner, Alsan, during Season 1. He's the king of Vanissar, struggling to reclaim his throne after Idhun, their magical realm, was taken by the dark wizard, Ashran, and his enforcer Kirtash.
Alsan's the chief warrior of the Resistance, never giving up hope that their kingdoms can't be taken back, so he's glad to have new proteges in their midst. But unfortunately, by the time Season 1 ends, he's shattered, physically and mentally, thanks to Kirtash and his lackey, Elrion.
It's a heartbreaking arc as Alsan really is selfless, prepared to do anything to help Jack and Vic as Chosen Ones so they could have a fortified team to take back what's theirs. It culminates in a run to Africa for the Staff of Ayshel, which only Vic can wield. Sadly, it's a trap. Kirtash ambushes Alsan, holding him hostage. But just when Vic's about to offer up the staff, Shail teleports them away as he knows Kirtash isn't a sorcerer of his word.
He believes Kirtash would have kidnapped Vic to use the staff and murdered Alsan anyway, so retreating was the best countermeasure, giving them time to regroup and build an assault on Kirtash's German castle. It's not the best choice, however, as Elrion's trying to impress Ashran, a powerful necromancer. Kirtash allows him to run his experiments to see how much Alsan can take, and this results in Elrion placing a wolf's soul into Alsan. It creates an unstable werewolf and as a result, Alsan struggles to tame the beast inside.
He's placed in a cell, losing his sanity as his body adjusts. But when he meets a feline woman -- similar to Wonder Woman's Cheetah -- he wonders if he can live as this hybrid. It all falls apart, though, when Jack rescues him and sees the woman get impaled by Kirtash, who basks in the kill. Alsan wonders if others like him have been killed by Kirtash and if he's truly destined to be alone, which informs his behavior when they escape to their base on Limbhad.
Unfortunately, Shail perished in battle, too, against Elrion, so Alsan's left broken, wondering what his real purpose is, and if he's truly up to the task. He locks himself away, trying to cage the beast -- unsuccessfully. At this point, he really feels like he'd blight the already tiny Resistance, and grows depressed.
Sadly, by the end of Season 1 of The Idhun Chronicles, this leaves the youngsters on their own, and a lot of it has to do with Alsan being scared to take responsibility. He can't cope without Shail and given his condition, Alsan flees, preferring to be a coward than a liability. Jack eventually falls out with Vic and goes after him but he's hidden away. Still, Jack won't give up because he knows Alsan isn't a monster; he's the best warrior they could ask to lead, and going into Season 2, a father-figure they so desperately need.