Elder Scrolls 4: Oblivion
If you dont know what black soul gems bring to the game, I dont think you've ever really used them. They are the only soul gem that enables a constant effect when used. Like golden saint filled gems in Morrowind.
Um, Black Soul Gems are grand soul gems that can capture human/argonian/etc souls. Every soul gem gives a constant effect when applied to armor, and every soul gem gives an on strike effect when applied to a weapon.
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