User blog comment:Lemursrule/BLEACH 366 Review: Goodbye for Now/@comment-387500-20120327195345/@comment-1351982-20120327195949

No that is impossible. A Zanpakuto can come from only one person, and one alone. Zanpakuto can have similar or in rare cases identicle abilities (Isshin's Engetsu), but a Zanpakuto comes from the soul itself, not spirit energy. That is one of the factors in how Ichigo regained his Soul Reaper powers. If the soul (as living as a soul reaper) dies, then the sword dies with it. Tosen meerly laid his sword on his friend's grave as a sign of respect. Please no more crack theories.