Sam went to work in the lab after that.
He just focused on that day's tasks regarding the three. After that, he went back to the Hub's secret room where the black smoke is captured. He channeled his energy into the sword. The spirit has been strengthened a lot.
It is of course nowhere near the strength of the spirit of shadow sword and the reaper. But it is still strong enough. The weapon with a spirit like that would be extremely attractive to an Astral plane cultivator.
Of course, this method is not exactly ideal in creating spirits. The forceful enchantment aside, the artificial growth that Sam created completely defeats the purpose have a spirit weapon. The preferrable method is like how Sam developed the spirit of the reaper sword over time.
The spirit generated with the numerous battles Sam experienced with that sword. So, whatever the growth, strength and changes the spirit experienced, they compliment Sam's style a lot.