According to the Wiki,
"Rosettes seem to be the most popular marking on Lioden currently, due to the mysterious nature of how they're passed on, and the fact that they can randomly pop up in any breeding. There are tons of user theories and conspiracies floating around regarding how Rosette works, but nobody truly knows—the code has yet to be cracked."

This could be taken to imply that they are truly random ("the fact that they can randomly pop up in any breeding"), but it can also imply that there is, in fact, a code ("the code has yet to be cracked").


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Exhibit A:
Cream Rosette

Mother was chased, but had the following:
Base: Cream (White Nose)
Mane Type: Normal
Mane Color: Brown
Eye Color: Grey
Slot 1: Onyx Ripple
Slot 2: Chocolate Top
Slot 6: Feline 7 Black

Dad had the following:
Base: Silver Grey (White Nose)
Mane Type: Sideburn
Mane Color: Lilac
Eye Color: Lavender
Slot 1: Feline 1 Dark Brown
Slot 2: White Tips
Slot 3: Feline 2 Onyx
Slot 4: Feline 6 Onyx
Slot 5: Feline 4 Onyx
Slot 6: Feline 1 Onyx
Slot 8: White Undercoat
Slot 9: Feline 3 Onyx
Slot 10: Onyx Lace
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Exhibit B:
Gold Rosette

Mom had the following:
Base: Dark Vanilla (Fallow Nose)
Mane Type: Diabolic
Mane Color: Lilac
Eye Color: Pink
Slot 1: Brown Mask
Slot 4: Feline 6 Dark Brown
Slot 5: Feline 4 Onyx

Dad had the following:
Base: Blush Rose (White Nose)
Mane Type: Diabolic
Mane Color: Manakbir
Eye Color: Peach
Slot 1: Feline 7 Ginger
Slot 2: Feline 1 Black
Slot 3: Rose Pelage
Slot 4: Maroon Pelage
Slot 5: Onyx Lace
Slot 6: Feline 4 Silver
Slot 7: Feline 2 Ginger
Slot 8: White Panther
Slot 9: Under White 4
Slot 10: Feline 3 Onyx
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Exhibit C:
Brown Rosette

Mom had the following:
Base: Dun (White Nose)
Mane Type: Tsavo
Mane Color: Maroon
Eye Color: White
Slot 1: White Cobweb
Slot 6: Vitiligo 3
Slot 7: Vitiligo 2
Slot 9: Vitiligo 4

Dad had the Following:
Base: Onyx (Brown Nose)
Mane Type: Savage
Mane Color: Unholy
Eye Color: Saffron
Slot 4: Feline 6 Onyx
Slot 5: Feline 2 Onyx
Slot 6: Feline 1 Onyx
Slot 7: Feline 7 Onyx
Slot 8: Feline 5 Onyx
Slot 9: Feline 3 Onyx
Slot 10: Feline 4 Onyx

Do you see a pattern?
I do.
Every. Single. Father. Has. At. Least. One. Feline. Marking.
See it?
Maybe parents with Feline markings produce rosettes, but it's rare.

Credit: Empress Tansy (#54105)