Evolution: Symbiosis Cards and Carnivorous/High Body Weight
According to the official FAQ (in Russian),


  Симбиоз
  
  Может ли животное (птица) со свойством хищник, находящееся под защитой симбионта (крокодила) атаковать его?
  
  Да, если симбионт (крокодил) уже накормлен.


In English, that would sound like,


  Symbiosis
  
  Can a carnivorous animal (a bird) that is protected by a symbiont (a crocodile) attack the symbiont?
  
  Yes, if the symbiont (a crocodile) has already been fed.


In my understanding, that means the protected animal cannot attack other creatures too, until the symbiont is fed.

P.S. See also A Living FAQ for Evolution: The Origin of Species in English