Heal is using any card that has a heal x max y ability. Eddie is a good one to use but you also have eggman and malicia as good options as well.
Eddy's good but if you're on a small budget you could get Ulawele, as far as Ulu Watu goes.
+1 what they're saying.
making a half deck with cherry and some pussycats would also help you go all pills on a strong healer then just DR-ing the enemy while healing to maximize your mission completion potential. You might not win the battle, but you'll finish the mission faster