Creature Feature Rules The following are special rules for Creature Feature. 1. Each deck can only have one creature type and each deck must have a minimum of 1/3 creature cards at all times even after sideboarding. Each sideboard can have 15 cards including more of the same creatures. However if you sideboard out a creature card you must replace it with a creature card from your sideboard in order to maintain 1/3 creature cards in your deck at all times. 2. Whether a card is the appropriate creature type is defined by what follows the word Creature under the illustration. Examples of Zombie creature cards are Scathe Zombies, Pyre Zombie, or Crypt Creeper because they all say Creature - Zombie. Crypt Creeper is a Zombie even though it doesn't say so in the card title, Crypt Creeper. Other examples of Zombie cards are Llanawar Dead. They are a Zombie Elf so they could be used in either a Zombie deck or an Elf deck. Creatures that are listed as both types can be used in any deck that has that creature type as its creature.  For instance if all creatures are Zombie Elf's that is a defining creature type and so all creatures must be of that combination.  Of course if they all are Zombie Elf creatures you could play a creature that is a Zombie Elf Wizard for example because it is a Zombie Elf despite the fact it is actually three creature types. 3. A card that would become a creature when special circumstances are met or that have an activated ability that turns them into a creature can be used in decks that have that as it’s creature type. Veiled Serpent could be used in a Serpent deck because it says in the text that the creature created from the enchantment is counted as a Serpent.  Treetop Village could be used in an Ape Creature deck because it says that it turns into an Ape creature when activated.  But these cards do not count towards the minimum of 1/3 creature cards per deck.  Lands, Enchantments, or Artifacts are examples of cards of this type. 4. Most creatures that previously stated that they count as a creature type has been changed to be that creature type. Sliver Queen used to say on the card that Sliver Queen counts as a Sliver. However it has now been reworded as Legendary Creature – Sliver. So you could use Sliver Queen in your deck as 1 of creatures required. 5. Non Creature Cards that create token creatures are playable only if the token creature created is of the type consistent with the deck. Call of the Herd could be used in an Elephant deck because the token creature is an elephant. If a card produces two different types of creatures it cannot be played in either creature deck because it creates creatures that are not consistant with the creature type of that deck. For instance, Decree of Justice creates both Soldier and Angel tokens so it cannot be played. If there are ever enough Angel Soldier creatures it could be played in an Angel Soldier deck. Currently there are none but that's not to say there could never be or that some other example might exist.  Sorceries, Instants, Artifacts, Enchantments, or Planeswalkers all have one or several cards that produce token creatures.  If you use any card that produces a token creature make sure it produces a token of the same type as the creature you are playing. 6. Creatures that create token creatures are playable in a deck even though the token creatures are not of the same creature type as the rest of the creatures in the deck. Deranged Hermit is an Elf. He could be used in an Elf deck because he is an Elf even though the creatures he creates are Squirrels. 7. Some creatures have changed type. When Hidden Horror was originally printed it was a creature type Undead. Later printings of the card listed it as a Horror. Some creatures have changed type even though they have never been reprinted. If you have a question about a creature type check Wizards Oracle rulings. 8. Mistform Ultimus is all creature types so it can be played in any deck even though it is printed as Legendary Creature – Illusion. Treat it the same as if it had every creature type listed in the subtitle. It counts towards your 1/3 creatures per deck because it is that creature type. (Legions FAQ) 9. Due to the fact that Wizards has decided to rename creatures from one type to another, sometimes for no apparent benifit or even one that makes sense, you can play a creature in a deck if the original printing of the card was one creature type even though it's been reassigned another creature type.  For instance in the example above, Hidden Horror was printed as a creature type undead.  If you have a deck of undead creatures you may include it in the deck even though the official creature type for it has changed to Horror.  You may of course continue to play it in a Horror deck. 10. Lords are allowed in a deck if they reference the creature type of that deck as most if not all have been renamed as the appropriate type. They do count towards the 1/3 creatures required. Example: Zombie Master may now be played in a Zombie deck as he is now a Zombie.  Or for example Goblin King is now a Creature - Goblin so he now counts as one of the required creatures in your deck.  Creatures which were previously Lords and gave bonuses to their creature type have now been reworded to give the bonuses only to other creatures of that type so read the updated Gatherer Text so you know how they work.  Lords are now a little stronger as they give the bonus to others of the same type.  For example Goblin King now gives Mountainwalk and +1/+1 to other Goblin Kings. 11. Kobolds may be played as Kobold Drill Sergeant, Kobold Taskmaster, Kobold Overlord, and Rohgahh of Kher Keep have all been renamed as Kobolds so there is enough of them to play. 12. Artifact and Legendary Creatures.  Due to the fact that Wizards is giving a creature type to most Artifact creatures and has changed the Legend creature type to Legendary creature while giving most a creature type, you can no longer play a deck of artifact creatures or Legends although you may include them in a deck of the appropriate creature type.  13.  Changelings can be played in any deck as they are all creature types.  However do note the following.  They do not count as one of the 1/3 creatures of the appropriate type that must be in your deck as they are a Creature - Shapeshifter.  And unlike Mistform Ultimus they are not all creature types.  Rather they have an ability, Changeling, which gives them all creature types.  Now for the complex explanation.  Mistform Ultimus has a Type-Changing Ability, or it changes the type of the creature.  Changeling is a Characteristic-Defining Ability, or it defines what the creature is.  What this effectively means is that Mistform Ultimus has every creature type printed on the card.  Example: Creature - Illusion, Soldier, Elf, etc.  A Changeling ability simply states that the creature is every type.  Functionally they work almost exactly the same.  However the key is that a Type-Changing Ability makes the creature all types, while a Characteristic-Defining Ability simply states that the creature counts as all creature types.  Bottom line is that you can't play a deck of Shapeshifters that have the ability Changeling and count them as a creature type.  They are still Shapeshifters.  They do not count as one of the required creatures in the deck, although you may add them to a deck of another creature type. 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