This week we will analyze cases of mixtures of sacrificial animals: valid offerings that became mixed with animals that can never be sacrificed (such as those used as payment, animals condemned to execution, or those involved in forbidden relations) and establish that once a single prohibited animal is mixed in, the entire group is treated as forbidden for sacrifice. The tractate then explores levels of nullification—whether mixing one prohibited animal into many permitted ones ever allows offering them, and identifies certain categories of items that are never nullified because they are normally counted individually. The later pages introduce practical scenarios of interchangeable animals or offerings—how to treat the mixed groups.