In the last part of the second season of Highschool DxD, there is a fight between Issei Hyodo and the White Dragon's host who was using a special skill called Divider that divides his enemies powers to half every time he uses.
Issei managed to get rid of it from the White Dragon as it was a Fragment of Magical Device attached to the White Dragon guy's accessories. Then, after Issei defeats that guy, he gets the Divider Fragment and fuses it with his Dragon Booster on his right arm.
I hoped he would use that dividing power later in the next season, but what happened to it? Where did that power go?