Overview
- Warner Bros. Games confirmed that the Mayhem Collection DLC and the Nintendo Switch 2 version of LEGO Batman: Legacy of the Dark Knight will arrive on September 18, 2026.
- The headline feature is an exclusive Arkham breakout story mission that casts The Joker and Harley Quinn as playable leads and reframes parts of the game from their perspective.
- Mayhem Mode is a timed, vehicle-focused challenge where Joker and Harley race through Gotham to smash landmarks and complete objectives while Batman, Robin and Task Force X pursue them.
- The DLC bundles a Sinister Pack of unlockable outfits, the Jokermobile and Batcave items drawn from DC media, and the Joker and Harley each get distinct gadgets and combat styles.
- Owners of the game's Deluxe Edition will get the Mayhem Collection at no extra cost and all platforms will receive a free Absolute difficulty update on launch day to raise the game's challenge; the DLC follows the base game's May 2026 release and its frequent comparisons to the Arkham series.