The setting is Ancient Rome. A priest is about to sacrifice a sheep to the gods—hardly abnormal. However, this priest has not yet completed his priest ed. classes, so he is still ignorant of some of the specificities of Roman ritual. In fact, hes about to make a terrible mistake.
The mistake is that this priest is about to sacrifice the sheep to Faunus (or Pan for you Greeks). Faunus, being the god of the wild, hardly wants to see one of his creatures sacrificed. If that were to happen, he could become quite angry, and we all know the only thing worse than a god is an angry, all-powerful god.
Therefore, your goal is to stop the priest from sacrificing the sheep. How? Guessing random Latin or English words, of course! (You have likely played the modern derivative, hangman).
Its time to stop reading this description and start saving some sheep!