Justice League
The incredibly dull series that lead to the much better Unlimited. Since it only had the seven characters, and I find Superman, Wonder Woman and Flash to be boring, it didn't sit all that well with me.
Also rewatched the first season of Metalocalypse.
Green Lantern: The Animated Series
The first 19 episodes were decent, then it went horrible with the last bit where an AI decided that because she got her heart broken, the only possible course of action was to destroy all organic life to ensure that "pain can never happen". It's like it was written by a 14 year old girl.