MagiStream

Description: A tiny bottle with a picture of a broken bone on one side, and an analog clock on the other. It has an unpleasant odour.

Usage: When sprinkled over an egg, the growth rate slows to a rate that almost stops it. Koi become as slow to hatch as Coal Wyrms, and Coal Wyrms seem to be purely lumps of coal. This slowed down growth speed will last until the egg has hatched, and the hatchling reaches 10% growth. They then return to growing as normal.

A way to possibly obtain low percent hatchlings, especially on ones that can be difficult (Event, etc).

How to obtain: New quest - from the keep.

Lord Rosario has recently been hard at work in the greenhouse labs. Students have been gathering around the doors for weeks to get a hint of what he may be working on, but to no avail. Rather than join the crowds, you have spent your time trying to invent a new spell to cure unsightly growths on your Dragon Turtles. After a particularly nasty explosion, you are ready to give up on the task, and storm out of your room, only to run into a much younger student holding a letter.
"Um," the boy stutters, startled by your shocking appearance. "I have a letter from Lord Rosario for all-" he isn't able to finish his sentence, as, your interest piqued, you grab the letter from his trembling hands. Raising an eyebrow at him, he quickly runs off to the next room along the corridor.
Closing your door again, you gently open the letter, finding a hastily scrawled note -

"Volunteers required. Special task available. Reward."

It's signed by Lord Rosario, so you shrug, tidy yourself up, and head down.

When you reach the greenhouse, an orderly line has been formed from the usual rabble surrounding it - mostly out of more experienced magi, like yourself. When you finally reach the greenhouse doors, you are shocked to see the area filled with Cukurba, Moss snails and Rekantum. The noise is almost unbearable.

"Ah, good, another volunteer?" Rosario pops up in front of you, holding a small notebook. "Very good. I've been working on a potion to slow down the growth of eggs, but I'm running low on creatures. Ideally, I need hatchlings of all of them - the growths from them are simply not potent enough as adults, you see," he talks incredibly fast, you almost lose track. Frowning, he writes something in his book.
"Still here? Right, I suppose you want to know about the reward. If you can bring me what I need, I'll give you one of the potions, alright?" he waves his quill at you, obviously ready for you to go. You shrug, thinking about what he said as you walk back to the stream.

Requirements: One hatchlings each of a forest rekantum, moss snail and cukurba. Hatchlings must be unfrozen and unnamed, but can be bred.

I really like this idea: it gives a fair shot to a 0.00 hatchling, but it will not drop their rarity so much like an item that gets you one automatically would.

I love the name's reference, too!