Using the Chart below you can gauge which of your heroes will help you out the most. Working towards S heroes and greater should always be the goal!
Here is a good infographic for GEN 5 for who to use for attacking
Curious when to upgrade which heroes, to know when they are strong enough?? The infographics show you when to swap to new gens!
Below show heroes and their generations. Along with stats to help you make an educated assessment on who to upgrade
