Dragon Ball Super: Super Hero is now out in theaters. And, while there is a lot of hype about how the movie puts Gohan and Piccolo back on the map of Dragon Bal power-players, Super Hero does also do something to advance the stories of Goku and Vegeta, following the events of Dragon Ball Super: Broly, and the anime's Tournament of Power arc. We know that (whether fully canon or not) Dragon Ball Super: Super Hero takes place during Dragon Ball Super's Granolah Arc in the manga – a story that saw Goku and (in particular) Vegeta make significant jumps in their power evolution.
Thanks to Dragon Ball Super: Super Hero, we now get a better idea of how at least Vegeta was able to unlock the power of Ultra Ego!
WARNING: SPOILERS FOLLOW!
The opening act of Dragon Ball Super: Super Hero sees Goku and Vegeta training on Beerus's planet with Whis and a surprise guest: Broly! Goku is attempting to teach Broly how to control his planet-destroying berserker rages while fighting and accessing his endless reservoir of power; meanwhile, Vegeta has an agenda of his own: mastering Jiren's mysterious meditation technique!
The Tournament of Power introduced Jired as the enigmatic alien from Universe 11, and the champion of that reality's ultimate hero force, The Pride Troopers. Jiren was Goku and Vegeta's ultimate opponent in the battle between realities of the Dragon Ball mutliverse, and he was certainly a unique one. Jiren's power level was said to be above Universe 11's God of Destruction, Belmond, and even when faced with the evolutionary abilities of Saiyan power and transformation, Jiren was never left behind. As seen in both the manga and anime (and video games), Jiren uses a form of deep meditation to tap into his deepest power levels and/or break through limits – a zen-like calm that is a stark contrast to a Saiyan's use of emotions like fury or excitement in battle to break through limits and reach new powers.
Vegeta being shown as interested in copying Jiren's meditation technique is actually a good detail for Dragon Ball Super: Super Hero to add. In the manga arc happening alongside the film's events, Vegeta has since also learned the technique of Spirit Control on Planet Yardrat, which further lets him master and control his own ki – or manipulate the energy of his opponents. Vegeta's energy manipulation led him to study the destruction techniques of the Destroyer Gods; during the Granolah Arc, Vegeta's Destroyer energy control gets married to a new Saiyan-style meditation technique to create the new form of Ultra Ego. Vegeta borrowing and learning form those who have bested him in a fight (Goku, Jiren) only makes that much more sense for his character.
Dragon Ball Super: Super Hero is now playing in theaters worldwide.