Excel Saga doesn't parody anime, it parodies the entire act of watching anime, treating every convention and restraint as permission to break it again. The show burns through jokes at such velocity that half the gags hit before your brain registers what's happening, and the other half hit three episodes later when you realize they were setting up the punchline all along. By episode 13 it literally restarts itself and admits it has no idea where the story is going. This is a show built for people who have watched enough anime to be exhausted by it, and need something that laughs at their exhaustion alongside them.
Excel Saga throws everything at the wall and doesn't care what sticks. The show follows a hyperactive teenage girl working for an underground organization plotting to take over the world, except nobody takes it seriously, least of all the anime itself. What you get is pure comedic chaos: genre parodies, meta-jokes that break the fourth wall, absurdist humor that shifts tone wildly from one scene to the next. One moment it's a spy thriller, the next a romantic comedy, then suddenly you're watching something completely unhinged that shouldn't work but somehow does. Excel's dog Menchi steals scenes by existing, randomly shifting between pet and philosophical narrator. The show operates on the logic of a fever dream written by someone who watched too much anime and decided to mock all of it at once. Every episode is a grab bag of whatever insanity the creators felt like animating that week. There's no real plot progression, no character arcs that matter, just an excuse for wall-to-wall jokes aimed at people who already know anime inside and out. If you want something that respects your intelligence through irreverence rather than sincerity, this is it.