I thought it could not be done. I have lost hope. I got to the point where I had only palp left and he just outhealed all damage I made with his leadership skill... But I eventually did. You just have to let the hate flow... Literally.
here is my swgoh, . I just got chopper to 7* today to get palp. I got depressed after he moped the floor with me. Even missed my daily free cantina energy...
So enough sobbing, down to business. I am writing this because there is one day left for this, and YOU CAN DO IT. I linked my swgoh.gg to show just how underdog my team was compared to him. They took 2-3 turns for one of mine. I kept trying to kill the guards first>vader>palp. Sounds good, doesn't work. Tried about 20 times. This evening, in blind rage, I decided to try to kill palp first. And what did he do? He started killing his own men with his heal. And the most important thing about that is that there is no shock that turn. Shock is the phoenix killer. No heal, no buffs, no bonus TM from ezra. Somehow that translates into no extra zeb protection even tho it's not a buff.
It took me 5 tries with some 1st turn resets on this strategy to down the event. The key plays to look out for are:
You will be stunned. A lot. If you get more than 3 stuns on first palp lightning, restart the event. Your chances of not losing that one are slim.
You will also lose. A lot. Try to find out the small parts you can improve on each defeat. In my personal example they almost never focused ezra so I didn't bother using anyting to save him, and he is the core of the team
Get Zeb to stun palp with hera/ezra assist whenever possible. This is not a sprint. You will need time to beat this team, but you also can't drag it out too much because shock will eventually keep killing your heroes.
Use Hera revive whenever you can, preferably with kanaan taunt. This is what I believe won me the game, Kanan soaking all the shocks.
So the core of the strategy is to not focus guards and instead get palp down to the point when they taunt. Then take out a guard. You will have breathing room since Palp will heal himself and you will have time to deshock. Repeat, take out the other guard. Then go all out on Palp (Palp has most HP so you can get a good head start by using hera expose basic) Leave Vader for last. While Vader can oneshot you with an incredible ammount of debuffs, You just have to pray for RNG. If you do not focus palp he will outheal you as soon as he gets rolling.
I wrote this mostly for new players that are in the same sauce as me: just hit that 7 star team and really want a legendary toon to add to the collection. The 1 mil creds dont hurt either. Good luck! Ask here if you have any questions.