Lazav and Soulbond

[Keyeto]

Probably a silly question but...since Lazav is becoming a new card and not re-entering, why would he remain bonded? Wouldn't he actually be getting a new instance of soulbond, and if so, wouldn't another creature have to ETB to trigger the ability?

Well, here's the thing. Being paired with the creature stays until you no longer have control of both cards. Lazav remains in the field the whole time, so he remains bonded with the creature. What changes, is the fact that his soulbond ability is different. The bond isn't broken, since he doesn't leave the battlefield or change control, the bond just does something different now.

[scarsabrex]

Also. Bonding isn't broken if the soul bond effect is lost to something like {turn to frog}