The Death of Lorcan Darcy is the 2017 Animated Storyline that was given the title The Death, Regeneration and Return of Lorcan Darcy.
In the story, The Darcy Kids are spending a weekend in Equestria until they discovers Princess Twilight Sparkle has killed someone they know. At the story's conclusion, Lorcan Darcy, the titlular character, die after got stabbed by Princess Twilight.
The crossover depicted the world's reaction to Lorcan's death in "Funeral for a Brother,"
"The Regeneration of Lorcan Darcy," a twenty chapter story and the eventual return of Lorcan in "Return of Lorcan Darcy!"