Raid strategy

Raiding, the ultimate test of team strength. Some suggestions... If you have Vader, use him! I used Vader on attempt one for over 13000 damage and the second time after using escape. With the door down, I did 13 grand the first time and 16667 the second time which was more than 5 ppl together could do together. Vader did a total of about 70000 damage! Secondly, If you have a healer left, use your strongest characters ( Vader, Rey, maybe phasma) first, escape them and then heal and reuse. The problem being that I've used them right off the bat all together before and after a certain amount of damage the Rancor becomes enraged and just eats them so I think there is a limit to how many times you can attack him before he is enraged. (If anyone knows, please speak up) Does anyone have any tips to share. They would be appreciated.