Kirigi

Kirigi is the Korean expert martial artist and master of an unidentified ninja clan. He is best known of training and shaping a majority of Bruce Wayne incarnations into to the masked vigilante we know as the Batman.

History
Bruce Wayne, having an urge to become the mysterious protector of his home town Gotham City, knew he needed someone to train him in the way of the ninja to become the stealthy, dangerous figure he longed to form into. So, he travelled to the blizzardy mountains of North Korea and entered Master Kirigi's palace in order to train with his skilled peers. After years of fighting, sneaking, and fixing tea, Wayne became the top warrior at the palace, an unstoppable fighter who left and became the Dark Knight we know him as today.

Personality and Traits
Kirigi is shown to be extremely hard and bitter towards his disciples, or at least to Bruce Wayne, showing him absolutely no respect until he completes his task. He could be genuinely cold, or this could be the commonly used teacher method to taunt the mentor's follower in order to give them enough rage to succeed. He is also an apparent racist who believes Americans are unskillful, blubbering fools.

Weapons and Abilities
From the small amount of screen time he has, Kirigi has never actually been shown in action. However, he must be one of the most; if not the most, skilled martial artists on the planet, as he was able to train hundreds, maybe even thousands of extremely dangerous ninjas as well has the completely unstoppable Batman and Lady Shiva.