Koi

Koi
Rarity	Legendary
Type	Walking
Base Stats
	+25,555
	x111,500
	x107,575
	x37,500
Chances
1x	4e-06% (1 in 25,000,000 chance)
1.25x	5e-06% (1 in 20,000,000 chance)
2x	8e-06% (1 in 12,500,000 chance)
2.5x	1e-05% (1 in 10,000,000 chance)
4x	1.6e-05% (1 in 6,250,000 chance)
5x	2e-05% (1 in 5,000,000 chance)
8x	3.2e-05% (1 in 3,125,000 chance)
10x	4e-05% (1 in 2,500,000 chance)
Rarity	Mythic
Type	Walking
Mythic Base Stats
	+38,333
	x167,250
	x161,363
	x56,250
Chances
1x	2e-08% (1 in 5,000,000,000 chance)
1.25x	2.5e-08% (1 in 4,000,000,000 chance)
2x	4e-08% (1 in 2,500,000,000 chance)
2.5x	5e-08% (1 in 2,000,000,000 chance)
4x	8e-08% (1 in 1,250,000,000 chance)
5x	1e-07% (1 in 1,000,000,000 chance)
8x	1.6e-07% (1 in 625,000,000 chance)
10x	2e-07% (1 in 500,000,000 chance)
Rarity	Legendary
Type	Walking
Shiny Base Stats
	+51,110
	x223,000
	x215,150
	x75,000
Chances
1x	4e-08% (1 in 2,500,000,000 chance)
1.25x	5e-08% (1 in 2,000,000,000 chance)
2x	8e-08% (1 in 1,250,000,000 chance)
2.5x	1e-07% (1 in 1,000,000,000 chance)
4x	1.6e-07% (1 in 625,000,000 chance)
5x	2e-07% (1 in 500,000,000 chance)
8x	3.2e-07% (1 in 312,500,000 chance)
10x	4e-07% (1 in 250,000,000 chance)
Rarity	Mythic
Type	Walking
Shiny Mythic Base Stats
	+76,665
	x334,500
	x322,725
	x112,500
Chances
1x	2e-10% (1 in 500,000,000,001 chance)
1.25x	2.5e-10% (1 in 400,000,000,001 chance)
2x	4e-10% (1 in 250,000,000,001 chance)
2.5x	5e-10% (1 in 200,000,000,001 chance)
4x	8e-10% (1 in 125,000,000,001 chance)
5x	1e-09% (1 in 100,000,000,001 chance)
8x	1.6e-09% (1 in 62,500,000,001 chance)
10x	2e-09% (1 in 50,000,000,001 chance)

The Koi is a secret Legendary pet in Bubble Gum Simulator. It could have been obtained by opening an Autumn Egg. The chance of hatching it was 1 in 25 million (0.000004%), or 1 in 12.5 million (0.000008%) with the Lucky Chances gamepass.