All you will need before reading this guide is all 6 hero slots unlocked. It also helps to have at purchased each of the cleric items at least once.

This build gives you 1 warrior, 3 clerics, 1 paladin, and 1 ranger.

For the first hero, you have two options:

Put every point into armour

or

Put two points into health, then the rest into armour

Either of these options works, but you will want to go with the first option in the early game.

For the second, third and fourth heroes, put every point into healing. This ensures that most of the damage the warrior takes is healed by the end of the round. It also boosts the party strength later on when you have the mystical cape and divine book.

For the fifth hero, you once again have two options:

Put one point into healing, one into armour, and the rest into damage

or

Put every point into damage

Both are good options, but unless you have purchased the banner of the knight at least once, it would be better to choose the second option. I have found that after purchasing the banner of the knight that the first option gets you past more floors than the second.

For the sixth hero, put every point into damage. I have found that it is more effective to have the damage dealing heroes after the clerics, as they then benefit from the mystical cape's stat increase on the round it is applied.

This isn't a guide to the perfect build, just to the one I have found works best for me. If you have one that works better for you, then use it.