I've been using Sakura with summoning slug, naruto with super tail beastvrashuriken, sasuke with his last ability, Kakashi with combat power instead of the lightening stun, and I had hanzo for poisoning. My cp is almost at 8m and they still won't die, it's ridiculous lol

It's only available during their events. You missed missed it by a month

It's dungeon 20-12

I really need help on beating 24-1. I have 7b combat damage and I'm using Sakura shining war, silver naruto, six path Obito, golden sasuke, susaano Kakashi, and hanzo.

Just beat it. You my friend are a miracle worker

I'm stuck on 22-12 now lol

Get about two good sealers (neji top left, Hinayana bottom right) and make sure neji has curse seal of wrath lvl 5 and hinaya has a curse seal of wrath lvl 3. If you have a kabuki, put him in the top middle and make sure he has his ability chakra scalpel. Then get the rest of your team to be taijutsu characters. Make sure all their special abilities only target one enemy, because you want to keep the tadpole alive. Once the tadpole releases its ability called "bubbles" it increase your taijutsu immensely. If your neji only does 1,000 attack the tadpole increases it to the millions.

Do you have any tips for 22-7?

I use Susa Kakashi, six paths Obito, naruto, Sakura, sasuke, and madara to beat it. Only took me one time.