This achievement requires you to use a number of different team sizes and custom Ensemble (Assist) attacks.
You must:
- Play 10 matches using a team of 3 members and using a custom Ensemble assist for each of them. (After you pick the character there will be 3 assists options, the first two are regular assists and the third one is the custom. Pick that one, map any button and you are good).
- Play 10 matches using a team of 2 members and using a custom Ensemble assist for each of them.
- Play 10 matches using a character individually.
After the end of each match you should see the "Saving..." message on the top right corner. If you don't, go back to character selection screen and pick a different team/character.
It doesn't matter which characters you use. It doesn' matter which colors you use. It doesn't matter the team size for player 2.
The achievement shall unlock upon the start of your final match.