User blog comment:Xilinoc/Ch. 557 - He Already Set His Life Aside/I Already Threw Away My Life/@comment-29183117-20131113144738/@comment-11051098-20131113151040

The secret technique, according to
 * Mangastream - "allows us to temporarily obtain immortal bodies"
 * Mangapanda - "allows us to obtain an immortal body"

It seems we have to wait and see.