How does Affinity work in Umamusume: Pretty Derby?

If you’ve been playing Umamusume: Pretty Derby for a while and are wondering why some training runs feel smoother than others, even with the same character, the answer is probably Affinity. It’s one of those mechanics that the game doesn’t explain too clearly, but once you understand how it works, things just start to click.

So, let’s break it down in simple terms.

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Everything you need to know about Affinity in Umamusume: Pretty Derby

At its core, Affinity is a hidden compatibility score between your main Umamusume and the two Legacies you choose at the start of Career Mode. This score determines how much of their power gets passed down to your trainee.

Affinity in Umamusume: Pretty Derby (Image via Cygames)

If your trainee's Affinity with the chosen Legacies is high, she'll start out with greater base stats, inherit more skills, and have a better chance of activating additional sparks during training. If her score is low, the advantages are drastically reduced, making your entire run with her feel quite slow.

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How is Affinity in Umamusume: Pretty Derby calculated?

It mostly depends on how well the parents line up with your trainee in terms of running style, preferred race distance, and racing performance. For example, if you’re training a Long-distance runner, it makes sense to pick Legacies that also specialize in Long races.

The closer the Legacies match with the trainee in race type and style, the higher the compatibility. Even the grandparents (the parents of your Legacies) come into play. These Sub-Legacies add another layer to the Affinity score, so it’s worth checking their specialties too before locking in your choices.

The game doesn’t give you an exact number, but it does show you a visual indicator of the Affinity rank. A double circle means the match is excellent, a single circle means it’s decent, and a triangle means the compatibility is on the lower end. You’ll want to aim for a double circle whenever possible, as that gives your trainee the best shot at inheriting a strong stat and skill base.

Pay attention to what kinds of races the Legacies won. Even if a parent has amazing stats, if they don’t line up with your trainee’s core traits, the Affinity won’t be great. On the other side, two decent Legacies with the correct qualities can give you a perfect double circle rating and a significant advantage.

A good Affinity gives your Umamusume numerous benefits right from the start. You’ll see boosted stats (those colored numbers above your base stats), early access to useful skills, and more consistent spark events that give additional stat gains. So, the next time you’re planning a new build, take a moment to look closely at your Legacy lineup.