Using equipment of different levels.
Before beginning this guide there are a few things that need to be explained to better the understanding of the following "wall of text".
Please also keep in mind that I will try to use the least confusing way of explaining everything because on more than one occasion people were not sure if a Mage has any need for PATK or if a Knight/Archer needs MATK.
One of the first things is knowing what each of the stats refers to:
MATK: Magic attack that is used by the Mage class.
PATK: Physical attack used by both Knight and Archer classes.
MDEF: Magic defence that is useful for ALL the characters.
PDEF: Physical defence again useful for ALL the characters.
*Note: The above names apply also for the units that players are able to recruit from the barracks however the units are not influenced by the refining of equipment but by their own daru upgrade.
Intellect: Useful only for the Mage. (Increases MATK by 4 and MDEF by 1)
Strength: Knight and Archer only. (Increases PATK by 4 and PDEF by 1)
Defense (on legendary items 40+ the name changes to Armor): Useful for ALL classes. (Increases MDEF and PDEF by 4 each)
Crit: Increases critical damage and can be used by all classes, but is a MUST for Archers and can help with the different types of character builds that Mages and Knights can come up with. (Mostly mages though.)
Endurance: Helps all classes and increases the health points.
HP: All classes benefit from it. (Increases the health points (life) of the hero or units, but again like in the case of the MATK,PATK,MDEF,PDEF the HP of the troops is increased by upgrading the troops in the barracks or academy.)
Charisma: Useful for all classes. (Increases the number of troops that the hero can have when fighting. Also depending on the enlightenment level and type on the troops, it provides boosts to the hero.)
Block: Helps all classes with damage reduction, especially useful for Knights since they can heal upon dodging damage.
While I could give you something like a "best combination" for each class I think each player should try to find what works best for them, but something to remember is that Defense/Armor, Endurance are something that you should always try to have in the stats and like I said I won't go into the "best combination" just find what is best around those stats especially if you are a free to play player just look at the small explanations for each skill and choose the ones that help your class (Mage/Knight/Archer) the most.
In Wartune there are three types of Refinement Crystals that can be used to refine equipment at different levels.
For refining level 1-29 equipment a Level 1 Refinement Crystal is used.