Most underrated cartoon series?

I posted the most overrated cartoon series question an hour ago. To me most of them are overrated because they are meant for kids. Although I understand people watch them for nostalgia and curiosity. Personally I do rewatch some of the series this year once as an adult not as a kid. Grossology, Kim Possible, Monster Allergy, Danny Phantom, Mucha Lucha. I still have many others to watch because I want to compare which of them are worth watching so I can pick the best ones to rewatch again and again if there is at least one. I hope… Turns out as an adult I have different expectations compared to when I was a kid in elementary school. I used to go nuts over many of my favourite childhood series and I loved them so much I couldn’t live without them. I remembered whining whenever I missed an episode, good old days…but now it’s different due to the fact there are many way better series for my age demographic. Children series are way too predictable for me. To me I don’t hate them they are just average imho but I don’t mind watching them. I preferred anime compared to cartoon series. The only ones I like are ATLA and Teen Titans (some of the Teen Titans episodes are hella boring no offense my favourite is gotta be about Terra), that’s it.

Most underrated cartoon series?
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