Perhaps the most salient distinction is the balls, or, in this case, round bean bags. (If you go Zoch’s official Cross Boule page, you’ll discover 12 different versions of Cross Boules – all the same, except for the patterns – the significance of which will be explicated later.)(You can also go to the official Cross Boule site - also in German.) The bean bagginess of the balls (traditionally made out of metal, stone, wood or other hard substances) is the key to the many wonders of Cross Boule, namely: you can play anywhere (I haven’t tried playing them underwater yet).
Your standard Cross Boule set comes with two sets of three beany boules, and one beany Jack (the smaller ball that serves as a target). This is pretty much exactly what you’ll find in your standard pétanque/boules/bocce set – except for the beaniness.
As for the rationale for purchasing more Cross Boule sets – each set is designed for two players. You’ll most definitely want to include your friends and theirs. And you want to make sure that each player knows which boule is hers
And now to the significant difference, the distinction that makes Cross Boule the major fun that it truly is: the rules.
So, you’re anywhere, and you call that the “starting area.” The youngest player, starting at the starting area, throws the jack (the smaller boule) anywhere else: under the couch, on top of the 8th stair, in the open drawer. Then players take turns, each throwing one of their beany boules, trying to get as close as possible to the jack in a manner most clearly reminiscent of horseshoes. Now, here’s the major part of the fun: the player who throws the jack also decides how the rest of the boules are to be thrown for the round (e.g.: two-handedly, between your legs, backwards, eyes closed, while wearing an oven mit). Then there’s the scoring, which takes intriguing advantage of the beaniness of the Cross Boule, awarding extra points if you can get one boule to rest on top of another, or if you can get it to land on top of the jack, or if you can make a pyramid out of three boules, or if you can get three in line. And before a round starts, you can redefine the playing area to include or exclude any property of your three-dimensional physical environment.
Allow me to illustrate (in German, but you don’t need the translation)