User blog comment:Xilinoc/Ch. 568. Hear. Fear. Here 2/@comment-1604252-20140212213631/@comment-5693502-20140213170252

I'd quite like to know who the other two Special War Potentials are.

Ichigo is one because he's the super hybrid.

Zaraki is one because in terms of raw power (not taking into account other skills) he is the most powerful Gotei 13 Captain (not including the now deceased Yamamoto). Also he was the only Gotei Captain to actually kill a Sternritter (3 in fact) in the initial invasion (again Yamamoto is not taken into account).

Aizen is one because it's Aizen.

I'm thinking Uryuu is one too (survived Auswahlen etc) but have no guesses as to who a fifth Special War Potential might be...