Aptitude, mood, weather and ground in numbers

Uma Musume: Pretty Derby race mechanics

An A in an aptitude is the baseline. S raises most of what it scales by 5% and Wit by 10%, and each grade below A takes something away, down to a tenth of normal at G for most of them. Mood moves all five stats by up to 4% either way.

Aptitude

Each trainee card grades a runner from S to G on two surfaces, four distances and four running styles, and each kind of aptitude scales a different part of the race. Distance aptitude has two numbers: one on the share of top speed that comes from the Speed stat late in the race, and one on acceleration, which only drops below normal at E. Surface aptitude scales acceleration as well, and running style aptitude scales Wit.

GradeDistance: speedDistance: accelerationSurface: accelerationRunning style: Wit

SDistance: speed: ×1.05Distance: acceleration: ×1Surface: acceleration: ×1.05Running style: Wit: ×1.1
ADistance: speed: ×1Distance: acceleration: ×1Surface: acceleration: ×1Running style: Wit: ×1
BDistance: speed: ×0.9Distance: acceleration: ×1Surface: acceleration: ×0.9Running style: Wit: ×0.85
CDistance: speed: ×0.8Distance: acceleration: ×1Surface: acceleration: ×0.8Running style: Wit: ×0.75
DDistance: speed: ×0.6Distance: acceleration: ×1Surface: acceleration: ×0.7Running style: Wit: ×0.6
EDistance: speed: ×0.4Distance: acceleration: ×0.6Surface: acceleration: ×0.5Running style: Wit: ×0.4
FDistance: speed: ×0.2Distance: acceleration: ×0.5Surface: acceleration: ×0.3Running style: Wit: ×0.2
GDistance: speed: ×0.1Distance: acceleration: ×0.4Surface: acceleration: ×0.1Running style: Wit: ×0.1

So a runner with a G in a race's distance gets a tenth of the Speed-based part of her late-race speed, which no stat total makes up for.

Mood

A runner's mood multiplies all five of her stats when the race starts: Great is ×1.04 and Awful ×0.96. On 1,000 Speed that's the difference between 1040 and 960.

MoodStats in a race

GreatStats in a race: ×1.04
GoodStats in a race: ×1.02
NormalStats in a race: ×1
BadStats in a race: ×0.98
AwfulStats in a race: ×0.96

Weather and ground

When a race's conditions are left to chance, the season sets the odds of each weather and ground. Rain brings soft or heavy ground, snow only falls in winter, and the rest of the year shares one set of odds. Skills that ask for a weather, a ground or a season read these.

Weather and groundSpring, summer, fall and cherry blossom seasonWinter

Sunny, firmSpring, summer, fall and cherry blossom season: 54.6%Winter: 50.05%
Sunny, goodSpring, summer, fall and cherry blossom season: 5.4%Winter: 4.95%
Cloudy, firmSpring, summer, fall and cherry blossom season: 23.4%Winter: 24.96%
Cloudy, goodSpring, summer, fall and cherry blossom season: 6.6%Winter: 7.04%
Rainy, softSpring, summer, fall and cherry blossom season: 5.5%Winter: 4.4%
Rainy, heavySpring, summer, fall and cherry blossom season: 4.5%Winter: 3.6%
Snowy, goodSpring, summer, fall and cherry blossom season: NoneWinter: 0.15%
Snowy, softSpring, summer, fall and cherry blossom season: NoneWinter: 4.85%

Skills in a race

A skill's duration is written for a 1,000 m race and grows with the race: the same skill lasts 2.4 times as long over 2,400 m. Most skills fire once per race. A unique skill gets stronger with the card's stars, from level 1 at 3 stars to level 3 at 5, and a parent passes on a weaker white copy of it through inheritance.

The skills list has every skill's conditions and effects in these numbers.