Mazinger Z

Mazinger Z and Mobile Suit Gundam are both one of the oldest and greatest Mecha/Super Robot anime's there is, both of these classics involve teens dragged into piloting a giant robot to fight other giant robots. Both Amuro and Kouji are apart of the Super Robot pilots "holy trinity" (which was started by Super Robot Taisen).  

In each episode is the same plot: Dr. Hell/Saikawa sends his Mechanical Beasts/Opposing Teams, Koji Kabuto/Tokuchi Toua runs to Mazinger/The Mound, background music resounds, and the battle/game begins. Many emotions and feelings are mixed in the battle/game, but in the end, Mazinger/Tokuchi Toua is the winner.  

If you like mazinger... then you probably won't like Taekwon V, but it might still be an interesting watch for you. Why? Because Taekwon V is basically a shameless rip-off of Mazinger. And they didn't even try to hide it when copying the robot design. 

Protagonist has to pilot a giant robot to save earth from episodical attacks by a non-human empire that seeks to conquer humanity. Both are adaptations of manga by Nagai Go that edited the original material into a more kid friendly version. Both are also so old school that they are among the first anime about pilotable mecha. 

Both Nagai properties were worked on contemporaneously by the same studio, and it shows. They're animated quite similarly (stiff figures, bright colors) and both feature a simple monster-of-the-week plot. I'm relatively sure that the two shows even share actors; Kouji and Akira are essentially the same character. 

Vintage mecha with episodical format as the protagonist fight monster of the week who is some sort of non-human threatening the humanity. As both are adaptations of Nagai Go manga from the 70's and made by the same studio, they have practically the same visuals and overall feel.