Mutations vs Morphs
A mutation (Mutt) is when a designated rarity trait has a borrowed trait from another rarity within the same base species, Leobuck, making it a Mutt.
A morph is when 2 rarity traits are mixed making a unique appearance.
Only non-breedable bucks that were not bred can use a mutation potion because they cannot breed to make mutations naturally.
Mutation examples:
Click here to see this 'bucks import
This is a Leobuck, a non-breedable species (Primal and snow racers excluded). If you click the link above, you will see that this Buck's rarity traits are Normal and Brawler. Having more than 1 rarity trait makes a character a "Mutt," as it's a mutation in the traits that cause more than 1 rarity trait.
click this link to see this 'Buck's import
This is an example of a natural Mutation 'buck aka Mutt. a natural mutation is done via breeding. As you noticed this 'bucks species is a crossbreed! It's rarity traits are Normal Buckleo and Pacific Lotus. Pacific Lotus is a Lycanbuck rarity trait, so this characters species mix is Buckleo and Lycanbuck, both breedable species. This character has rarity traits from both normal buckleo and pacific lotus.
Click this link to view this character import
This 'buck is an example of a rarity mutation (mutt) on a 'buck that was not bred. For a breedable to have a rarity mutation trait that is not from breeding it would need a designated MYO that states it, such as "Rare Buck Mutt". Leobucks (minus Primals and SnowRacers) cannot use such MYOs.
Morph examples:
click this link to view this character import
This 'buck is a normal lycanbuck. As you can see when viewing the import it only has one rarity trait. It's ears however are not Normal lycanbuck ears, they are morphed with Bearing Blitzer and Desert lotus ears.
For Morphs, you do not need the rarity trait that you are mixing in the rarity trait list as it's not a defining trait! However, you can only morph traits that are within the species listed. Since this 'buck is a lycanbuck, it may only have morphed traits that are of Lycanbuck.
Morphs are limited to their rarity. Normal and Rare bucks can only morph normal and rare traits, they cannot morph anything outside their rarity. (Normals can use rare traits)
Morphs may also use any traits that are below their rarity, IE an exclusive buck may use rare or normal traits to morph.
You cannot morph any rarity trait that is not of the species. If you have a crossbreed you may morph traits from those species that are in your mix. Please be mindful that morphs are not a defining trait, meaning there will need to be a defining trait of your mix.
Morphs are also limited to their designated locations on the body. You cannot morph something that isn't there. If a buck has feathers on the head you cannot morph those feathers on the ear, as the head and ear are two different locations on the body. You cannot morph traits into a different trait, IE using a morph pot to change the ears from a terror to a night plague. That is not morphing that is a Mutt trait. Morphing requires a mixture of 2 or more traits.
click here to view the character import
If you click to see the import, you will notice this 'buck is a Terror x Seraph, however the seraphs wings are morphed with seraph X's wings giving them that feathered bat wing look. The paws are also morphed with terror and seraph, using the paws of the terror while adding the dew claw of the seraphs. The defining traits for this 'buck are the Tail for seraph as terrors can only have docked tails and fangs/ears from the terror.
Note: When using morphs, 'bucks will need a defining rarity trait and overlapping traits do not count. For example; If you had a normal buckleo x alpha and you used all the traits from an alpha/and or morphed traits and the only normal buckleo trait you used was the cat tail. This would not work as it's an overlapping trait with the alphas as alphas can have any tail, meaning it's not defining.
Conclusion
Mutation potions are only for Leobucks that cannot breed/are not a genos. They cause the leobuck to have more than 1 defining rarity trait causing that 'buck to be a Mutt.
Morph potions are only for breedable bucks/ genos. They allow traits to be mixed causing a unique appearance that is NOT a defining rarity trait. They do not need the rarity trait in their mix in order to morph but it does need to be within their species(s).