Best martial arts fighter in comics

[yodajones]

"Your zest for transmogrifying super-science is only exceeded by your zeal for kung-fu treachery!!!"

[Lego Nightwing]

I don't know that I would put her in the top 5. But how about Black Canary?

[amamerko]

Lei Kung the thunderer
Immortal Weapons(especially Prince of Orphans n Fat Cobra)
Mr X
Winter Solidier

[Knatty Dreadnok]

In no particular order...

Shang Chi
Lady Shiva
Bronze Tiger
Black Canary
Silver Monkey
Elektra
Daredevil
Iron Fist
Captain America
Deathstroke
Batman
Nightwing
Badger
Storm Shadow
Snake Eyes