Affinity

The better the affinity, the higher the chance of getting a lot of inherited sparks during the two inspiration events during the training, which happen in early April. The affinity is decided by a variety of things. At a baseline, each uma has hard-coded affinity with every other uma, which is derived from various things usually related to the real-life umas. Dirt racers tend to have good affinity with other Dirt racers and such. This affinity applies between the uma you’re training and her parents, and between her and her grandparents. Every uma has 0 affinity with themselves, which is significant for grandparents. You can check these numbers on Gametora.

Triangle is 50 or less affinity, double circle is greater than 150 affinity. There’s no significant jump here, 149 affinity isn’t massively worse than 151. Affinity is linearly useful, 149->150 is the same increase as 150->151. But, the double circle is a good target when you don’t want to bother calculating everything.

You can increase this affinity by doing races. Currently, you get +1 affinity for each graded race you win on both the parent and the grandparent. So, if you won 10 graded races on Oguri, then trained a Teio with the Oguri as a parent and did those same 10 races, you would get +10 affinity for the Teio parent, making it easier to get double circle affinity for your runs. If the other grandparent also did those 10 races, you would have +20 affinity.

If both parents did the race, there’s another bonus. So, if the other parent was a Mayano who did those 10 races, it would be another +10 affinity, for +30 total. Doing races is also good since it gives you more SP, which means more skills, which means more chances for white sparks.

However, later on this gets changed to be +3 per matching G1, with G2s and G3s no longer counting. This applies retroactively, so your parents’ affinities might change after that update. As such, just focus on the G1s when making your parents in this way. They give good stats anyway, you should be doing them with some frequency even on normal runs.