Shanks talks about how a man can grow by both defeat and victory
and he stated he was part of countless battels
it's true he is been part of big epic wars ever since he was merely 12 or even before than that
but at same time
in 957 WG implied Shanks crew is undefeatable and impregnable
Whitebeard , Kaido , Big Mom , Shiki , Rocks and ...
all of them lost more than 1 wars or another crew overpowered them in one way or another
so do you think any one defeated Shanks in a war?
or he is just like Gold Roger : undefeated
if yes, who?