Ikoria: Lair of Behemoths — Sundered Bond

Ikoria: Lair of Behemoths—Sundered Bond is a novella written by Django Wexler, published as an e-book by Wizards of the Coast on April 7, 2020. It tells the story of the set of the same name.

Blurb
Lukka is a proud captain of the Coppercoats, the elite military force that defends Drannith from the savage monsters lurking outside its city walls. For the Coppercoats, the only good monster is a dead monster. Lukka's world is forever altered when he unexpectedly forms a mystical connection with a ferocious, winged cat. But such bonds are high crimes in Drannith, punishable by death. Running for his life, Lukka flees the very home he was sworn to protect. Now an outcast monster "bonder," Lukka must survive the wilds of Ikoria while being ruthlessly hunted by his former brothers-in-arms, including the sadistic General Kudro. With help from planeswalker Vivien Reid, can Lukka learn to tame his newfound powers before he wields vengeance--and an army of nightmarish monsters--against his beloved Drannith?

The bonding
Lukka's special intervention squad is called upon to neutralize a monster, and they find out it is a winged tiger. It's smarter than any monster they've encountered. The cat kills three of his four squad members, only stopping when Lukka suddenly and unwilling bonds with the monster. He learns that it is being commanded to attack the city by a magical force, and gets an image of orange crystals. He passes out.

Outcast
When he wakes up he's in the hospital. Despite his fiancée Jirina's pleading, her father, General Kudro, decides that Lukka has to be imprisoned. Kudro has heard of people bonding with monsters, a fairly new thing, and he doesn't trust them. Jirina helps Lukka escape by faking her own kidnapping. The visiting planeswalker Vivien Reid senses some weird magic and investigates it, finding Lukka. The magic she was investigating was bonding magic. She scares off his pursuers.

Pursuit
Jirina is assigned the job of tracking down Lukka, being sent with a bunch of mercenary hunters. Lukka and Vivien find the winged tiger, about which Lukka has mixed feelings. Mentally communicating with it knocks him out again. A big crystal formation called the Ozolith turns out to be the source of a voice, and an urge forcing monsters to attack Drannith. After Lukka reawakens, Jirina and the hunters find Lukka and Vivien but they escape by riding the winged tiger. The hunters decide they need an airship to follow the flying cat, so they end up visiting the flying boat city of Skysail, where they hire a ship of skypirates.

Lukka and Vivien find some other bonders. Apparently monsters can communicate with each other via crystals. The bonders travel with Lukka and Vivien to the Ozolith.

The battle at the Ozolith
Everyone gets to the Ozolith and there is a three-way fight. Lukka, Vivien, and the bonders, versus Jirina's hunters and pirates, versus some Nightmares that are guarding the Ozolith. Lukka connects his mind to the crystal. He talks with whoever is using the crystals for nefarious purposes, and they imply they are from a different plane. They also don't seem to care about the lives of people on this plane or to take responsibility for what they have done. They still decide to help Lukka and let him use the Ozolith's power. Lukka commands all the Nightmares to attack the hunters, which leads to the pirates fleeing. Lukka decides he wants to use this power to control monsters for the sake of Drannith. The bonders and Vivien aren't happy with this idea, as they see animals as friends, not slaves. Eventually, this gets to the point where Lukka decides to take control of the bonder's monsters. Vivien says she thought he was a good person, but that he has gone too far. She tries to fight him, but has to flee with the bonders while Lukka goes mad with power.

Marching on Drannith
Lukka loses track of the winged tiger, but it has rescued Jirina when the pirate ship was attacked by monsters. It flies her back to Drannith where it gets shot and captured, and she falls from it, getting seriously injured. Jirina wakes up in the infirmary. General Kudro wants her to execute the winged tiger, but Jirina is against the idea because she thinks it's working with Lukka. General Kudro thinks executing it will get rid of whatever suspicion people have of Jirina after seeing her carried into the city by a monster, but it's also a test to see if Jirina is still loyal to the city or is on the side of the monsters now. Jirina is ordered to perform the execution but refuses.

Lukka tries to find Jirina with his growing army of monsters, but can't find her in the ruins of the pirate ship or anywhere else. One day he gets a vision from the winged tiger and sees Jirina refusing to execute it. He comes to understand that the winged tiger saved Jirina, even though Lukka had never commanded it to. He understands that the winged tiger protected her because it knew Jirina was important to him. He then witnesses the winged tiger being executed. He gathers his monster army to march on Drannith but is apparently still intent on using the army to defend Drannith and win back his old life.

The death of Kudro
General Kudro thinks the oncoming monster army is a threat and plans on using his daughter as an unwilling weapon against Lukka. They march out to meet the monster army. Vivien and one of the bonders take out Jirina's guards to have a talk with her. They leave after she says she's a prisoner now and can't help them.

Lukka wants to parlay with General Kudro. The General agrees to it, but only so Lukka can be assassinated. He wants Jirina to do it, saying she'll be back in the good graces of the city if she does it. The meeting happens, Jirina refuses to kill Lukka and tells him that General Kudro wanted her to assassinate him. Lukka calls his monsters to kill everyone but Jirina. He stabs General Kudro to death himself. He thinks he'll be able to talk his way back into the city and its leadership. Jirina slashes at him but only grazes him, then jumps into a river to escape and gets washed away. Lukka calls her a traitor and says she can die along with everyone else.

The fight for Drannith
Jirina is rescued by Vivien and the bonder. They mention Narset as someone who could help them, but don't know where she is. They meet up with another bonder and head towards Drannith. Jirina ends up taking control of the city's defenses, and many bonders agree to fight against Lukka.

In the fight, once things start to turn against Lukka, he tries to take control of all of the bonded monsters, but the power of love makes it harder. In the attempt, he ends up overloading the Ozolith and causes it to explode. This causes his planeswalker's spark to ignite and he planeswalks away.

Aftermath
Drannith rebuilds with more tolerance for bonders. Jirina is a colonel now. It is unknown who caused problems with the Ozolith in the first place. Lukka wakes up on another plane, still with a fraction of the power he had over creatures when channeling the Ozolith, and possibly still crazy. He vows to get home one day.