Best equipment

[RPGFan]

The highest attack power weapons are the final upgrade paths for the noble weapons which are obtained in the story, each of final tiers (monarch weapons, and evil monarch weapons) have the same attack power but one reduces physical damage by 50%, and the other reduces magical damage by 50%.

Yamato and Tsubasa each have a stronger weapon, the hero great sword and the hero spear, obtained by fully upgrading their starting weapons (Loss great sword, and mentor spear), but they have fewer slots and no bonuses (and they look basic).

You can obtain most of the upgrade materials from enemies in the final dungeon, material tower. Make sure to buy the thief gem from the in game store to increase drop rates from enemies.

the strongest weapons from the base weapon tree are : Excalibur, legend muffs, Wilhelm, Longinus spear, and Durandel.

As for the armors, the final upgrade tier of the starting armor is the best ones I found. You can find the second armor upgrade for some characters in the treasure warehouses in some towns.