the very bottom bar actually causes something related to which badges you chose to use happen... mario does abilities *example: mushroom causes you to be healed, bro highers sp, power causes a strength boost to happen...* luigi's badges strengthen it and make it harder to boost *good does a low amount and causes you to get em with good to excellent, great is stronger with great to excellent, excellent is strongest and can only get raised by excellent*
The best badge combination I've found is the Excellent only badge for Luigi and the starting healing badge for Mario. It restores 50% of their HP and removes all status effects.