11-Risking his life on eating poisonous mushrooms only to find out that he gets another Life 1up.
mario doesnt really have a degree on mushrooms and their effects but he knows which ones to eat.

10-Moustache,mario without his mustache is like a gamer without his hands.
his famous moustache is really giving mario the character he has to be,it would just be wrong to see mario without it.

9-His long career in pluming.
ever since we know mario he was a plummer,yet he doesnt have the tools that plummers have such as a hammer,but he understands that you can get inside pipes.

8-Italian origin.
He used to say "maama miaaa"after losing!i wonder if he could speak fluent Italian.

7-His competitive relations with his brother luigi.
luigi has always been competing with mario and always stood by him,he even went to find mario once,but yet again no one cares.

6-Sounds he makes when he loses or wins.
you see mario saying something clever after each level clearance or after losing.

5-The Love for mushrooms and mushroom land.
we never see a rain in any of the levels yet we find mushrooms all around.

4-Going from heavenly levels on the start and ending up in hell.
it always starts from a greenland and ends up in a place just like hell.why does he even go that far?princess peach or a simple adventure?

3-His suspicious relationship with princess peach.
after all these year we dont even know what kind of relationship they have.

2-His hobby,Cosplay and wearing different costumes.
he will wear anything aslong as it is usefull for him, and no he doesnt care what you think afterwards.

1-Looking for princess peach in wrong castles,that leads to rescueing unwanted servants who have mushrooms on their heads!
i dont really get the concept of characters that have mushroom on their head.what are they anyway?atleast mario likes his adventures,and doesnt giveup that easy and shouldnt he be king by now?he has rescued them more than 20 times now!