Chronozoa

• WWizards of the Coast2007-02-01
  Official Ruling
  Chronozoa's last ability creates two Chronozoa tokens that each enter with three time counters and have all of Chronozoa's abilities.
• WWizards of the Coast2007-02-01
  Official Ruling
  If Chronozoa becomes a copy of another creature and is put into the graveyard from the battlefield, no copies will be created. If another creature becomes a copy of Chronozoa and is put into a graveyard from the battlefield (with no time counters on it), two copies of Chronozoa will be created.
• WWizards of the Coast2007-02-01
  Official Ruling
  The ability checks to see if Chronozoa had no time counters on it at the time it was put into a graveyard from the battlefield. This doesn't necessarily mean it must have been sacrificed due to vanishing; it could have been put into the graveyard some other way (say, while the sacrifice ability of vanishing is on the stack).

Rulings via Scryfall