User blog comment:B214/Season 3 discussion/@comment-74.58.219.123-20150606205617

Hey guys, I watched episode 10 with spanish subtitiles on Youtube. If you don't wanna know what happens before seeing the English sub, then I suggest you don't read what follows. It contains SPOILERS!!!

It appears Loki's curse indeed activated Issei's Juggernaut Drive. Not only that, later in the episode, it created a second Issei who appears evil and Rias seems to be cursed as well. Azazel reveals that following his defeat against Issei, Loki cursed both Issei and Rias and wants to use them to create Ragnarok instead of him. Apparently, the curse is activated because the person has negative feelings Inside. Issei's feelings is due to Raynare. It appears Rias has something inside of her as well as she's cursed. Even more strange, Loki confronted Odin and sealed himself away meaning he might not return. It appears this evil Issei created by the curse is the last villain of the season.

I love how Loki's curse makes a better storyline than the light novels.