Is Jinx dead in Arcane Season 2?

No. Jinx is alive in Arcane Season 2. There are several strong hints pointing to her survival: a shimmer of purple streaks away from the explosion, Caitlyn smiles as she spots the ventilation shafts in the Hexgate schematics, which Jinx could have used to escape, and the final scene with a blimp flying away echoes Powder's past dream of riding in one, followed by Jinx's disorienting perspective.

Is Viktor and Jayce dead in Arcane Season 2?

No, Viktor has been confirmed by Christian Linke himself to return in future shows. He also mentioned that other characters might come back to life.This is just my speculation, but since Jayce and Viktor are essentially two sides of the same coin, and Jayce is an in-game champion, he’s very likely to return as well. Plus, Mel is still alive, which opens the door for a potentially emotional reunion between her and Jayce.

Is Heimerdinger dead in Arcane Season 2?

No, Christian Linke has confirmed that Heimerdinger is still alive. So, the theories that he might respawn in Bandle City, leading to Riot introducing more Yordle champions, could actually be true.