Who is it that killed Zephyr's crew and then became a warlord? So I just watched the One Piece Movie - The Battle of Z and it left me wondering who it was that killed Zephyr's crew (while he was in the Navy) and then became a warlord? It says he was a devil fruit user and that is why he acquired that weapon on/as his arm to take out all the devil fruit users he could. 

Does it get explained anywhere in the manga? Any helpful information would be appreciated!
The Warlord who killed Zephyr's crew is not named even in the current chapter of the manga.

Nevertheless, it was stated that the pirate who killed Zephyr's crew became a warlord during the timeskip. Therefore, there are only three possibilities: Trafalgar Law, Buggy and the currently unnamed warlord. However, it it also not yet revealed whether the unnamed warlord is a devil fruit user.