A new mishnah - it's very long - listing the groups of people who have no share in the World to Come. Such as, the generation of the flood (those who were not saved in Noah's ark). Likewise, the spies of the Book of Numbers. And many others. Where the biblical texts about each of these groups intimate that they are punished in the next world, and/or losing the World to Come. Plus, an investigation into the animals that Noah brought into the ark - 7 kosher animals and 2 non-kosher animals, "husband and wife." Including concerns about cross-breeding among the animals. With the ark itself perhaps determining which animals were worthy of joining the rescue.