How do I restore health to units for galactic battl

A lot of teams can heal themselves, not so much at lower levels though.  These teams would do better at Galatic War.  Phoenix was a good example of a team that can heal up.  I guess Mon Mothma and OG Imperial Troopers,  OG Bad Batch, OG Night Sisters are others that would also do this.  I'm unsure how developed they'd have to be for that to kick in to a degree where they'd heal right back up for the next match though.