Choose a creature type. Destroy all creatures that aren't of the chosen type.
8/25/2017 Once Kindred Dominance begins to resolve, no players may take other actions until it’s done. Notably, players can’t try to save their creatures after you’ve chosen a creature type.
8/25/2017 You must choose an existing creature type, such as Vampire or Cat. Card types such as “artifact” can’t be chosen.
8/25/2017 You can’t choose multiple creature types, such as “Cat Warrior.” A Cat Warrior is both a Cat and a Warrior. It’s affected by anything that affects either type and unaffected by things that affect non-Cat or non-Warrior creatures.