Oh gosh.. so much to choose from.
Choppers past, so sad.
Usopp fighting luffy, gosh that was uncomfortable to watch.
Robins past revealed, and her yelling. "I want to life!" Later on.
Merry's death.... jesus, One Piece for me will just always be.. that show that made me cry over a bloody ship!
That entire song sequence Brook had, where his crew slowly dies one by one around him, and we see glimpses of him being alone on that ship for fifty years, yet he keeps singing that one song to hold on.. So many feels!
When the Straw-hats all broke apart and Luffy weren't able to safe just one of them, all gone.
Bon clays sacrifice.. that was just.. Bon-bon! Noooo!
Ace's and WB's death.. oh gosh..
And I am pretty darn sure that... yeah, Kyro's past will be another tear jerker in the anime! It made me feel in the manga :,(
Those for me are the cry moments that really stuck out to me in One Piece... so hard to choose just one.