With a clear plan in place, all that remained was to cultivate step by step.
While Yinsen worked hard, Yoruichi trained desperately as well—she chose the orthodox path of improvement, striving to raise her normal-state Combat Power and strengthen her control over her transformed state. Her strength would not undergo explosive leaps, but it was steadily improving.
Over that year, Yinsen worked hard to digest the Black Dragon's power. However, this was not something he could accomplish in one go; he could only spend time grinding away at it slowly.
After a year, Yinsen had only barely "digested" his "excessive" Dragonification state into an ordinary Dragonification state—the appearance he had taken when fighting Frieza before.
The dragon horns on his head were smaller, there were no scales on his body, his wings were smaller, and he no longer had a tail.
At that point, he had two options: continue excavating the Black Dragon power buried deep within himself, or keep digesting the power he currently possessed until it was completely absorbed before seeking out the deeply hidden Black Dragon energy.
He did not think for long before deciding to completely digest his current Black Dragon power first. He felt that this might allow his body to better adapt to that power, perhaps speeding up the process afterward.
Just as Yinsen was training hard, Son Goku, who had been away for a year, finally returned to Earth.
Compared to Yamcha, Tien Shinhan, and the others who had returned long ago, Son Goku had thoroughly enjoyed this trip. He had wandered around for an entire year without returning even once to rest up.
As Son Goku and Krillin recounted their journey, Yinsen learned that Son Goku had encountered many things during his travels and had unexpectedly learned what had happened to Vegeta.