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The Complete UMA Affinity Guide

UMA affinity — the bond system at the heart of UMA Musume and similar raising games — is one of the most impactful yet frequently misunderstood mechanics in the genre. Affinity isn’t merely a cosmetic relationship meter; it is a direct multiplier on your support card’s effectiveness, a gatekeeper to exclusive bond events, and ultimately a key determinant of your UMA’s final stat ceiling. Players who master the affinity system consistently produce stronger race candidates than those who ignore it.

Having analysed hundreds of UMA raising runs across multiple meta seasons, I’ll share everything you need to build an optimal affinity strategy from day one.

How the UMA Affinity System Works

Bond Level Thresholds

The affinity system in UMA-style raising games uses a point accumulation model with discrete milestone thresholds that unlock increasingly powerful bonuses. Each milestone represents a qualitative shift in the relationship and the rewards it provides. The thresholds are typically structured as follows: 0–79 points (no bond), 80–249 points (1 heart), 250–999 points (2 hearts), 1,000–2,999 points (3 hearts), 3,000–5,999 points (4 hearts), and 6,000 points for maximum 5-heart bond.

Affinity Gain Sources

Affinity points accumulate through multiple in-game actions, each with different point values. Joint training sessions are the most reliable source, typically awarding 7–10 points per occurrence depending on support card skills. Bond events — the story vignettes that trigger when specific affinity thresholds are crossed — provide large one-time point bonuses of 30–50 points. Some support cards have passive affinity generation skills that add 1–3 bonus points per training tick regardless of which character you’re training with.

Support Card Affinity Bonuses

Each support card in UMA-style games provides escalating stat bonuses as affinity level increases. A support card at 1 heart might provide a 5% training effectiveness bonus; at 3 hearts this increases to 15%; at full 5-heart bond the bonus reaches 25–35% depending on the specific card. When multiplied across 6 support card slots and compounded over 24+ training turns, this difference produces radically different final stat totals.

Optimising Your Affinity Route

The most efficient affinity strategy prioritises the support cards you plan to train with most heavily. If your race strategy revolves around Speed training, max-bonding your Speed support cards first yields the highest return. Use the UMA affinity calculator above to determine exactly how many sessions each card needs to reach your target bond level given your typical support card bonus percentages.

Advanced Affinity Strategies

Advanced UMA players use what’s called the “affinity banking” strategy — deliberately avoiding training sessions with support cards you don’t intend to use heavily, saving your limited race turns for cards where the affinity bonus delivers maximum return on investment. This requires precisely knowing your point totals and thresholds, which is exactly what the UMA affinity calculator above enables.

Another advanced technique is event triggering optimisation: bond events award large affinity point bonuses, but they also consume turns. Some players time their training sessions to hit bond thresholds at specific points in the race scenario where the event’s story rewards align with their UMA development needs.