If you trigger that Blood Artist effect four times in one turn, you transform Sephiroth to his reverse side, Sephiroth, One Winged Angel
If youre playing him aggressively you can rack up a good amount of lore, and then when he is banished, you get to draw a card to keep going
However, as weve just seen, The Emperor [27-098L] also has a powerful Auto Ability that triggers when he is put into the Break Zone
Grading, as with any form of collectible culture, does increase the value of the card
Sometimes because of their collection value, sometimes because newer cards might be in better condition, and sometimes for the very simple fact that theyre cooler (ie, the art)
For example if you choose poison you can add one to your opponents poison count