Spoiler
CALLISTO MANTIS
GENERAL: Callisto Mantises are native to the islands of Callisto, as their name suggests. About the size of a balled up fist, they thrive in warm, tropical climates, taking up residence in the brightly colored flora of the island and feeding on the small insects and mammals that would devour such organic gems if given the chance. They blend with their environs so well that they are commonly imported into the mainland by being accidentally mistaken for the very plants they inhabit.
EGG: This egg appears no different than an ordinary flower bud: ovoid and shiny in general, with variegated streaks of green running vertically from the base to the top. It even comes to a slight point at the top. If you look close enough, you'll notice the slightly pink tinge the edges have are actually a pair of giant oblong eyes peering out at you!
HATCHLING: This little nymph is a voracious eater! Its white body is thick and pedal shaped, with tiny pink and purple freckles beginning to emerge. It spends hours standing deceptively still on your hands and shoulders only to pounce on stray insects and dried leaves like a miniature kitten. Although you never see its bright white eyes move, you're pretty sure it's watching you at all times. Whether out of adoration or hunger, you're not sure you want to find out.
ADULT: Your Callisto Mantis emerged from its final molt an entirely new creature! It still has that intense stare, but its tiny body now looks quite striking with all those floral stripes. Its arms are covered in razor sharp spines and its lacy wings look equal parts efficient and graceful. It darts around so quickly that you start to contemplate the possibility of teleportation. You suddenly understand why such a small creature is revered by martial artists from all stretches of the globe!
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STONE TURTLE
GENERAL: Sometimes, the key to survival is to lie so low and inconspicuous that people mistake you for harmless, inanimate objects. No one knows how long the Stone Turtles have roamed the hazardous shoreline of the Raza forest, but the earliest discovery of the craggy creatures was documented by a young Magi expeditionary team. The team remained lost in the forest for a entire week before they discovered that the reason they could not retrace their steps was because their crude stone trail markers were getting up and waddling back out to sea! Eventually, having grown weary of their journey, the group retired to the top of a large boulder and lit a campfire for the night. Imagine their surprise when their entire campground stood up in protest!
EGG: This egg is heavy and brown, with light and dark marbelization running along its oblong form. The only thing that differentiates this egg from the smooth water-worn river rocks you found it amongst is that it pulses softly with the rhythm of a tiny heartbeat.
HATCHLING: Other Magi make fun of your pet rock and your pockets may be wearing a little ragged due to tiny obsidian claws constantly paddling through them, but you ignore it. This Stone Turtle hatchling is adorable, from its cute little glossy black eyes to its grey and green moss-dappled scales. It may not exude energy or personality, but you're pretty sure it likes it when you tap out drum beats on its thick mottled shell and it sure is a good listener! Whether tucked in your pocket, defending your scrolls from thieving breezes or basking in the radiant explosions of your failed spells, this patient creature remains loyally at your side.
ADULT: Your pet has matured into a fabulous specimen of a mature Stone Turtle. It spends its time milling around the halls and sunbathing in the garden, which somehow leads to you spending all your time replacing valuable herbs and repopulating the koi pond. You've tried reprimanding its inconsiderate actions and the turtle's watery eyes look genuinely upset by your accusations and threats, but in the end it's just as stubborn and thick as its namesake.
I really think it's gorgeous. Usually the only pretty bugs are like butterflies and stuff, but this makes praying mantises (plural?) look beautiful too! 
Both would be nice additions but like Yunyi said, the mantis would definitely be something new.
