Zeta Gundam is the sequel series to the original show. The original will help tremendously in getting accustomed to the universe and mythos, but watch it in the condensed movie trilogy version; trust me, it's better. And it's still long. But it sets you up for Zeta nicely.
I picked Zeta because it gets kind of mind-blowing in its tendency to kill people of in shocking and effective ways. And the finale is something else.
Victory Gundam is another good recommendation. It's set much farther down the original timeline's rabbit hole, but it's pretty unrelated because of it.
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Sir Chris Police ~Ace Detective in Homicide~
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