Luffy:
How is the guardians? Is the ML a protagonist or an antagonist?

It's a spoiler, so I can't tell you. ;) 

I have created a voting list with the name 

'Dramas with badass ML'.

 So do vote so we can find out the most badass ML is out there. 

Mr. Sunshine

Goblin

Descendants of the Sun

Rurouni  Kenshin

The Bridal Mask

Hotelier

City Hunter

Healer

King2Hearts

Doctor John

Kill It

Lawless Lawyer

 Chia6:

Mr. Sunshine

Goblin

Descendants of the Sun

Rurouni  Kenshin

The Bridal Mask

Hotelier

City Hunter

Healer

King2Hearts

Doctor John

Kill It

Lawless Lawyer

Is the ML in King2Hearts really badass? I remember h being a spoiled little Brat for much of the drama

 Luffy:

How is the guardians? Is the ML a protagonist or an antagonist? 

Protagonist...whose one act seeking revenge was unpardonable..and hence his end was.....

Guardians/The Lookout could have been  tamong  Top 3 shows if the ending was not like that