To be honest you're still quite a bit in the early stages of the game and have not too many ninjas just yet, so i just picked something that worked with your first gold summon.
Fuguki - hopefully will tank a majority of attacks to reset mystery, tankier as hp goes down and has 2x lowfloat to highfloat chase
Wind main - has a repulse to knockdown chase x2, flower guard and 15 chakra on chase.
jiraiya & sakura - both have knockdown to lowfloat so we can complete a full cycle twice through chases
sakura - heals a % of dmg taken, gets shielded from flower guard, and summons slugs to heal team with mystery(slugs take up space 4x)
jiraiya - his mystery is not [prompt] so he wont use it immediately / it will use up his standard attack basically