Exclusive: LEGO Batman: Legacy of the Dark Knight Deluxe Edition - Mayhem Collection DLC Trailer Showcases Joker and Harley Quinn Story Mission

During the gamescom Studio livestream, IGN had the exclusive reveal of the trailer for the Mayhem Collection DLC for LEGO Batman: Legacy of the Dark Knight Deluxe Edition. The trailer provides an exciting glimpse into the new story mission featuring Harley Quinn and The Joker, the introduction of Mayhem Mode, and the Sinister Pack.

The Mayhem Collection DLC will be available at no extra cost to all Deluxe Edition owners on September 18, 2026, which coincides with the game's launch on the Nintendo Switch 2.

The highlight of the DLC is the new story mission starring Harley Quinn and The Joker. The duo will team up to 'orchestrate a breakout from Arkham Asylum with a going-away party Gotham City won't soon forget.' Harley Quinn will come equipped with her trusty hammer, a Fun Gun loaded with Confetti and Bubblegum, and she can summon her beloved hyenas, Bud & Lou. The Joker brings his Paintball Pelter and Boxing Glove, along with a 'fast-paced, agile combat style focused on speed and mobility.' Players can also unlock outfits for both characters inspired by past Batman media, including The Dark Knight Returns comic series and Batman: The Animated Series.

Mayhem Mode unleashes Harley Quinn and The Joker across Gotham City, tasking them with time-limited Mayhem Runs. In each run, they must return to Amusement Mile before time expires, all while being chased by Batman and Robin. Players earn LEGO studs by smashing everything in sight, completing challenges, and battling A.R.G.U.S. Agents and members of Amanda Waller's Task Force X, including Deathstroke, Killer Croc, Captain Boomerang, Deadshot, King Shark, Polka-Dot Man, and other 'notorious DC Super-Villains.'

The Sinister Pack includes themed outfits inspired by popular DC comic book issues and action figures, plus a new vehicle and Batcave customization options. The full list of items in the pack is as follows:

Additionally, on September 18, an enhanced 'Absolute' difficulty level will be added as a free update for all players. This new difficulty mode will demand 'greater skill, awareness, and precision in combat.'

LEGO Batman: Legacy of the Dark Knight launched on PS5, Xbox Series X/S, and PC in May 2026. In our review, we praised it for 'a strong open-world Gotham and trademark Lego slapstick humour powers a fantastic plastic parody of Batman’s greatest hits.'

For more, check out everything announced from Opening Night Live and what else to expect from the rest of gamescom.