Board Thread:News and Announcements in game/@comment-32510639-20171225152546/@comment-32271305-20171226235430

The one in the video stacked his ATK for more than 40 times, so I'm pretty sure his stacks are unlimited. He's not the only one that can do that, other examples being AGL and PHY Kaioken Goku, INT Ultimate Gohan, TEQ SSJ Future Gohan and STR Perfect Cell. And now TEQ Vegito Blue, too.

But then again, you don't need to stack his ATK for 40 times to beat the actual events, so it only matters up to a certain point.