The Seaponies are brightly colored seahorse-like creatures who dwell in the rivers and lakes of Dream Valley. They love underwater polo and can perform elaborate songs and dance numbers. They were first released in 1983 and only appeared in the two original specials. The Seaponies are based on the Hippocamp, a mythological creature shared by Phoenician and Greek mythology. A sub-line of the Seaponies called Baby Seaponies debuted later in 1985 and later in . Some additional Seaponies are shaped like merfolk. Hippogriffs and Hippocamps are introduced in the 2017 and Season 7 onwards of . They are a "hybrid sub-species" of ponies able to shapechange between forms to better adapt to an aquatic or mountainous environment. Crystal Ponies are inhabitants of the Crystal Empire in . They appear as Earth Ponies with a few distinctive features. Their form changes depending on their mood. When they are sad and depressed, their manes and tails are flat and unstyled, their ears are always folded down, and their coats have a greyish hue. When they're happy (without the Crystal Heart), their manes and tails revert to different styles, their ears are up as normal, and their coats have a brighter hue. Additionally, mares get their decorations on their heads/hair. When in a more jubilant mood (with the Crystal Heart fully powered), all the Crystal Ponies retain their "happy mood" form and their bodies magically transform into a translucent crystallized form. The Crystal Heart also crystallizes the Mane Six, Spike, Shining Armor, Princess Luna, Princess Celestia, and Princess Cadance as well, albeit briefly (possibly reverting to their original forms as they exit the Crystal Empire). Kirins are a race of unicorn-like creatures with lion-like traits. They are known for being kind and truthful, and their culture emphasizes theatrical and musical entertainment. When angered, they take on a beast-like form referred to as "Nirik" ("kirin" spelled backwards). They were formally introduced in the season eight episode "Sounds of Silence", where the Kirin character Autumn Blaze revealed that after their anger and bickering destroyed their own village, the elder Rain Shine forced them to bathe in an enchanted river that suppressed their ability to express emotions or speak (however, "foal's-breath" flowers are able to reverse the effects). The Pony Friends is a sub-line of My Little Pony, first released in 1986.