Creature types have been around since Wizards of the Coast printed the very first set of Magic cards, Limited Edition Alpha. One could argue even Gamma playtest cards implied a Creature type in that the Creatures themselves were of various types (e.g., Drudge Skeletons and Shivan Dragon).

At the time, these Creature types were largely created for flavor purposes. It was cool to attack your opponent with a giant, fire-breathing dragon but, it didn't make a difference whether the Creature was a Dragon as opposed to an Elemental or Djinn, as far as the rules were concerned.

In fact, there were only a couple of instances where type was relevant from a rules standpoint. These were the original Alpha "Lords." Lord of Atlantis pumped Merfolk and granted them islandwalk, Zombie Master granted Zombies swampwalk and a regeneration ability, and Goblin King pumped Goblins and granted them mountainwalk.

The rest, along with their subtypes were simply for flavor.

The Growth of Creature Types Matter

Over the course of the game's history, Creature types quickly accelerated in relevancy.

From Dwarven Soldier caring about being blocked by Orcs to Wellwisher gaining life for each Elf on the battlefield, types have evolved to be a highly relevant characteristic in Magic: The Gathering.

Over time, these Creature-types-matter cards have grown not only in number, but also in power level. Gone are the days where "Lords" were the only cards that made types relevant.

In modern Magic, the right threshold of types could mean far more than just pumping your team. One powerful example is Gilt-Leaf Archdruid, which draws its controller a card whenever they play a Druid spell.

That's not all. Tapping seven Druids activates a backbreaking ability: gain control of all Lands target player controls.

Anybody interested in making the most of this card, has to be sure to play enough Druids. Fortunately, there are hundreds of them, so finding enough to play even in a singleton format such as Commander won't prove too difficult.

What happens when a powerful "Creature type matters" relies on a type that isn't as ubiquitous? Consider Zeriam, Golden Wind, printed only once in Dominaria United Commander. Zeriam's power comes from the fact that it is self-propagating. Its controller is rewarded whenever a Griffin does combat damage to a player, and the reward is the generation of more Griffins.

This seems like it would be a lot of fun to build around in Commander, except there aren't a load of Griffins in existence to choose from. Scryfall lists 55, and while that is more than enough for a playable, on-theme deck, it does include some outdated and outclassed cards.

Does the Zeriam, Golden Wind Commander player really want to play four mana 2/2 flyers like Unyaro Griffin or Teremko Griffin? Probably not. Not to mention some Griffins aren't mono-White, so they wouldn't qualify with Zeriam at the lead.

How can some of these powerful type-matters cards be fully maximized without sacrificing card quality?

Changing Creature Types in MTG

Forutnately, there is a subset of cards that have the powerful ability to change a card's Creature type. These cards are available to any typal deck, so long as the deck is supporting the color requirement.

Here is a rules breakdown, with Xenograft as an example.

The printed rules text for Xenograft isn't too lengthy. "As Xenograft enters, choose a creature type. All creatures you control is the chosen type in addition to its other types." It sounds simple enough.

Additional rulings can be found in Gatherer. In 2011, two additional rules were added:

• You must choose an existing Magic creature type. (Fortunately, there are hundreds to pick from, so there is plenty of opportunity to add a personal touch).
• Creature cards not on the battlefield and creature spells are not affected. (This is not the same for every card).

Then in 2017 one more ruling was added to address replacement effects:

"Replacement effects that modify creatures of a certain type as they enter the battlefield will apply (or not apply) after you apply this effect. For example, if Warrior is the chosen creature type and you control Bramblewood Paragon, a Runeclaw Bear would enter the battlefield with an additional +1/+1 counter."

Even these additional rulings don't add much complexity, and changing or adding Creature types to a card remains pretty straightforward.

The only exception would be if multiple effects that altered a Creature type were in play at the same time, particularly if they're using replacement effects (i.e., changing a Creature's type from one to another).

Fortunately, most of these effects grant Creature types as an addition to any base types, so this layering component comes up rarely.

Most Powerful Creature Type Changing Cards

The motivation to change Creature types is clear. All that's left is identifying the most powerful cards that can alter types -- luckily, there are a handful to choose from.

Leyline of Transformation

One powerful example is Leyline of Transformation.

Being a Leyline, this Enchantment has the added benefit of starting a game on the battlefield if it's in your opening hand.

Other than that, it follows the standard templating that appears on most instances of this effect. When it enters, choose a Creature type. Creatures you control are the chosen type in addition to their other types.

This card also modifies Creature spells you control on the stack and even ones who aren't on the battlefield yet. With these extra abilities, you could name Rebel and then use Lin Sivvi, Defiant Hero to search up any Creature in your deck and put any Creature card from your graveyard onto the bottom of your library.

Conspiracy

Conspiracy is another example in Black.

This one costs five mana instead of four and doesn't include a way to cast it for free, but if you're looking for a type manipulator in Black, this is one of your best options. Note that Conspiracy also grants the Creature type to cards in your graveyard, hand, and library in much the same way as Leyline of Transformation.

Unnatural Selection

If you're interested in changing specific Creatures and not altering every single one you control, you could explore Unnatural Selection.

While this one requires one mana to activate for each Creature you wish to target, Unnatural Selection offers the benefit of changing your opponents' Creature types. There are plenty of ways to exploit this effect. One powerful combination is Unnatural Selection and Spirit Mirror.

With both Enchantments in play, you can pay one generic mana to change any of your opponents' Creatures into a Reflection. Then use Spirit Mirror's zero-mana activated ability to destroy that Reflection Creature. Rinse and repeat.

Standardize

While most of the time, these types of effects appear on Enchantments and permanently impact the game state while they remain on the battlefield, there are exceptions. If you're in the market for an Instant that alters Creature types, then Standardize is your answer.

With a handful of Creature-type payoffs at your disposal, Standardize could become a massive blowout your opponents never saw coming. Better yet, use Standardize to name "Reflection" and proceed to destroy every one of your opponents' Creatures with Spirit Mirror -- all for just two Blue mana.

If you'd rather gain control of all your opponents' Creatures instead, you could also combine Standardize with Peer Pressure (as long as you have the widest board when it resolves).

Mirror Entity and Maskwood Nexus

If you don't want to bother with naming specific Creature types, or if there's motivation to grant your Creatures all types, there are a couple Changeling-related options.

For example, Mirror Entity and Maskwood Nexus can turn Creatures into Shapeshifters with all types.

The Mirror impacts only Creatures you control. Maskwood Nexus works on Creatures you control, Creature spells you have on the stack, and cards you own that aren't on the battlefield. Both have their place in the right deck.

Omo, Queen of Vesuva

Finally, there is Omo, Queen of Vesuva, which can gradually place everything counters on your Lands and Creatures.

The benefit of this is that a Land with an everything counter is every type and a Creature with an everything counter on it is every type.

Since Omo only modifies one card at a time, this is a slow method. If you have reason to change only specific Creatures, however, this could be a powerful effect.

Wrapping It Up

This isn't an exhaustive list, and Wizards of the Coast is likely to print more Creature modifying cards in the future. It merely provides a starting place to work from and investigate further.

For now, the Creature type changing ability appears to be relegated to Esper colors (with Omo, Queen of Vesuva adding a splash of ).

There are no Red cards that offer this effect, though there are certainly plenty that care about Creature types. Fortunately, with Maskwood Nexus being an Artifact, every color has at least one option for this type of Creature-changing effect.

One last card worth shouting out is Artificial Evolution, a Blue Instant from Onslaught that changes the text of a card by replacing a Creature type with another Creature type.

This is a fun, powerful way of modifying your combo-centric Creature typal cards to meet your needs.

Using Spirit Mirror as an example, you could use Artificial Evolution to change the word "Reflection" to be any Creature type (e.g., "Elf" or "Sliver"). That way, you could start knocking off your opponent's Elves or Slivers without having to change their types.

Artificial Evolution can lead to some crazy, flavor-warping combinations. Imagine a Sliver Queen pumping out Skunks!

These combinations and more await in the world of Creature-type matter decks. The best part is, as new cards are printed that focus on types, these type-changing cards become even more relevant. If you have any interest in digging into a Typal theme, these are fantastic cards to throw in your next deck.