Board Thread:Questions and Answers/@comment-10797017-20130624101208/@comment-26420452-20130711082724

I think there are two possible theories about Renji and Rukia being overwhelmed by the Reishi concentration in Hyōsube's palace: 1 - They haven't been properly training before and feel its effects only now 2 - Hyōsube's palace is nearer to the Soul King's palace than the other one's, and the Soul King excudes continuously vast amounts of Reishi at all time (and that's why he's the lynchpin of the worlds) Hyōsube probably invented Kidō. What makes me think that is his monastic-like attire. And as for Ichigo, he won't feel any difference in Reishi concentration when he goes there and they actually expect it; he's a monster in terms of Reiatsu.