Troop Grade
Troop grade is perhaps the single most important factor that determines the power of a hero. IMHO it trumps equipment and attribute wash. Raising the tg makes the crit/dodge/block hero to crit/dodge/block more often, the healer to heal more, and the dancer to fail less.
In addition, a hero whose tg is higher than his enemy's is believed to get roughly a 5% attack bonus for every grade higher, and a 25% def bonus for every 10 grades higher. (I did not verify the numerical accuracy of this claim but I feel that it falls within the ballpark from what I've seen so far.)
Renascence
Rena is the best way to raise tg. Each rena can effectively raise the tg by anywhere from +1 to +9 grades when the hero grows back to the original level. Rena is very time-consuming so you want to maximize your chances of a good rena.
A common mistake by beginners (myself included) is to rena a hero at assembly level 51. That results in the worst possible rena of +1. To improve your chances of a good rena, always keep the assembly level at least 9 levels above the hero's rena required level. By doing so, you should be able to get renas between +5 and +9, with +7 being typical.
Troop grade is perhaps the single most important factor that determines the power of a hero. IMHO it trumps equipment and attribute wash. Raising the tg makes the crit/dodge/block hero to crit/dodge/block more often, the healer to heal more, and the dancer to fail less.
In addition, a hero whose tg is higher than his enemy's is believed to get roughly a 5% attack bonus for every grade higher, and a 25% def bonus for every 10 grades higher. (I did not verify the numerical accuracy of this claim but I feel that it falls within the ballpark from what I've seen so far.)
Renascence
Rena is the best way to raise tg. Each rena can effectively raise the tg by anywhere from +1 to +9 grades when the hero grows back to the original level. Rena is very time-consuming so you want to maximize your chances of a good rena.
A common mistake by beginners (myself included) is to rena a hero at assembly level 51. That results in the worst possible rena of +1. To improve your chances of a good rena, always keep the assembly level at least 9 levels above the hero's rena required level. By doing so, you should be able to get renas between +5 and +9, with +7 being typical.