| Mastema vs Xiaoyu | 7–5 | 58.33% |
| Mastema vs Kazuya | 7–5 | 58.33% |
| Mastema vs King | 5–6 | 45.45% |
| Mastema vs Lili | 5–4 | 55.56% |
| Mastema vs Yoshimitsu | 4–4 | 50.00% |
| Mastema vs Lars | 4–3 | 57.14% |
| Mastema vs Jun | 3–4 | 42.86% |
| Mastema vs Eddy | 5–2 | 71.43% |
| Mastema vs Jin | 5–1 | 83.33% |
| Mastema vs Lee | 5–1 | 83.33% |
| Mastema vs Reina | 4–2 | 66.67% |
| Mastema vs Hwoarang | 0–5 | 0.00% |
| Mastema vs Zafina | 4–1 | 80.00% |
| Mastema vs Nina | 4–0 | 100.00% |
| Mastema vs Dragunov | 3–0 | 100.00% |
| Mastema vs Leo | 3–0 | 100.00% |
| Mastema vs Victor | 1–2 | 33.33% |
| Mastema vs Paul | 0–2 | 0.00% |
| Mastema vs Bryan | 0–2 | 0.00% |
| Mastema vs Steve | 2–0 | 100.00% |
| Mastema vs Jack-8 | 0–2 | 0.00% |
| Mastema vs Asuka | 2–0 | 100.00% |
| Mastema vs Alisa | 0–2 | 0.00% |
| Mastema vs Panda | 2–0 | 100.00% |
| Mastema vs Leroy | 2–0 | 100.00% |
| Mastema vs Law | 1–0 | 100.00% |
| Mastema vs Shaheen | 1–0 | 100.00% |
| Mastema vs Kuma | 1–0 | 100.00% |
| Mastema vs Azucena | 0–1 | 0.00% |
Limitations
This data is often requested to give insight into which characters you have more trouble with than others, but it is not particularly helpful for that. The main issue is that it is heavily skewed by how strong the opponents you play are.
For example, this data suggests my worst matchup is clearly vs Reina, but that's just because most of those games are vs Yagami.
There is a way to account for this being worked on. The central idea is to assign each matchup a rating vs you which adjusts based on the result, much like the regular rating but also based on the rating of each player. With this, it would give a better summary of how well you perform vs each character.
In the meantime, this page is here to present the data as requested.