In Harley Quinn Season 4, the Legion of Doom has tried hard to really break Gotham. Unfortunately, they haven't been efficient. Harley has been able to take out some of their members during her own redemption quest, while Poison Ivy did way more damage as an eco terrorist in Season 3.
Source：https://www.cbr.com/harley-quinn-season4-terra-tefe-volcana-natural-disasters/
