They all do the same thing, and are functionally the same card, but that hardly matters - Final Fantasy and Magic mega fans are going to want to have them all to display in a pretty binder
Expert Interview Emchompite
Whereas normal version of RUG/Arabian Aggro can easily lose to the card, this version at least plays a mix of countermagic to handle critical threats like The Abyss, and after sideboard you can also bring in things like Tranquility, Whirling Dervish, and Concordant Crossroads (which acts as a one mana removal spell for The Abyss because they are both Enchant Worlds, and also makes all of your attackers hasty, shortening the clock)
Both are legendary in more than name, with The Masamune giving first strike when attacking and forcing a foe to block, while also giving double triggers for creatures dying
Green will be used only postboard, when Grudges are sided in and thats why I concluded that if I want to have Ancient Grudges in the sideboard, I should add Stomping Ground to the sideboard as well and bring them together