Danzo is good for lighting teams and few fire teams and he is able to save your ninjas from death easily even saved me from blitz teams when i timed it correctly. Mei is one of the best ninjas in the game and for a reason. Her passives are insane first, barrier for water and fire that when is active it can poison two targets, 25% more dmg to male characters on top of that, plus she can accupanture, immobilise and a aoe ignite that hurts a lot. Now it depends on the roll you want them. But if you want a team with mei our fellow players above gave some that are also great