Waluigi is the greatest hero of all times. He transcends time and space to protect us from darkness whenever necessary. He is the hero none of us deserve but we all need.
First of all, he is the strongest of the fifteen characters that could defeat Thanos(even with the Infinity Stones) in seconds. His power and battling prowess are unrivaled. He is even stronger than Star Platinum or Killer Queen’s Bites ZA DUSTO. Aqua is merely an insect compared to him. Even Big Nigga would have trouble leaving a scratch, let alone defeating him. There is no mistake that Waluigi is the most powerful entity in the universe. We should be thankful that he is not evil.
That power would make even the mightiest Chaos Gods submit.
Other than his immense strength, he is also a the best god tier waifu. Neither Makise Kurisu nor Thosaka Rin stand a chance against his charm. If you could choose between world peace, being a pokemon master and giving Waluigi a material form where would you want Waluigi to appear?
As a bonus, he is one of the most memeable characters. The Waluigi memes are first class.
There are little to no memes as good as the ones with Waluigi.
Hopefully I have convinced you that Waluigi doesn’t get all the respect he deserves and that not only is he the greatest hero ever, but he is also the savior of mankind.

A deep, thoughtful, sensitive man with a mustache.

God and the savior of this earth. Often known to make the WAH noise.

the one guy who just want some love but got rejected so he went mad and became a bad guy

Waluigi is our Lord and Savior who is the goddess of charm and lust. He will not be in smash due to him being overpowered in the community. This is a loss.
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The closest thing to a God on this Earth, and way too holy and powerful for petty conventions such as Super Smash Bros. We worship him day and night with waas.