Thought to be deceased since the beginning of season 2, last episode saw Darkseid back with a vengeance. And now, in order to defeat the ultimate threat, the Justice League has to join forces with Lex Luthor's Legion of Doom. It's everyone, and I mean EVERYONE, vs. Darkseid and his forces in hands down the best television battle this decade.
I'm not spoiling what's happening, but you'll definitely want to cheer after the episode's ever, especially if you're a Superman fan. And Justice League/Unlimited has brought great entertainment since its debut in 2001. I'm going to miss it quite a bit.