I don't recall Mifune being able to hit more than 1 team with his mystery...

Oh and for the ones who don't have expensive ninjas, here are some more ninjas whose mystery can hit multiple teams:

Torune

100 Puppet Sasori (only if 3 or more puppets are on the field)

Normal Sasori (skillbooked)

Normal Konan (only if targets are tagged)

Normal Deidara (only if targets are ignited)

Normal Utakata (only if targets are poisoned)

Normal Sasuke (skillbooked)

Konoha Traitor Orochimaru (skillbooked + using his mystery 2nd time)

Fire Main

Pakura

A couple more more costly ninjas:

Fu (only if targetted unit is asleep)

Hokage Minato (only if targetted unit is tagged)