Expansions to the first LEGO DC modular building – 76300 Arkham Asylum – are heading in an unfamiliar direction in early 2026.
Expansions to LEGO76300 Arkham Asylumfrom last year took the building up and outwards, adding more parking space, an extra floor, or making the building wider. We even explored one such expansion in a recent feature, but a bit of inspiration from LEGO Harry Potter has seen the community head in a new direction.
76417 Gringotts Wizarding Bank Collectors' Edition, which is due to retire this July, offers something new for modular models. It can be displayed on top of an underground section, increasing the overall profile of the build despite the lack of anti-stud space on the baseplate.
No other official set has replicated this at the time of writing, but the community have discovered this idea's potential by applying it to 76300 Arkham Asylum.
Early 2026 has seen a couple of underground expansions to 76300 Arkham Asylum, including from the_bricked_cave. Their build adds two extra layers to the Arkham Asylum build with sewers, a lab, and plenty of room for characters not included in the LEGO set.
Takemenorth on Rebrickable has a more subtle take, just incorporating a sewer system for Killer Croc to inhabit. The villain's spaces in 76300 Arkham Asylum are limited to a standard cell and a manhole cover with claw marks. They've expanded on the latter while keeping the standard baseplate, using tiles to have the official set sit loosely on top of their expansion.
MAC's MOCs on YouTube was the first to this idea, adding an underground section to 76300 Arkham Asylum back in September 2025. They also opted to include a sewer system, which is the one common factor between the three underground expansions. It would appear that the community agrees that Killer Croc doesn't have enough dedicated space in the official set.
Despite the existence of 76417 Gringotts Wizarding Bank Collectors' Edition, an official underground expansion to 76300 Arkham Asylum seems unlikely since any expansions to modular buildings are usually other surface-level buildings. The community has demonstrated the potential of underground spaces in modular models, either way. In fact, fans did the same with 76294 X-Men: The X-Mansion in 2024.
76300 Arkham Asylum is available now with 2,953 pieces and many exclusive minifigures for £269.99 / $299.99 / €299.99. Check out the set and another expansion option in our recent feature.
Support the work that Brick Fanatics does by buying your LEGO using our affiliate links – thank you!
Comments
Be the first to comment!