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.

If you reveal your entire library and reveal fewer than X creature cards of the chosen type, you'll put the cards of the chosen type that you did reveal onto the battlefield and shuffle your library.

You must choose an existing creature type, such as Vampire or Cat. Card types such as “artifact” can't be chosen.