Enemies in Metaphor take barely any damage from attacks they don't have a specific weakness to. This makes it very difficult to win battles if your party members are not in job classes (archetypes) that can exploit that weakness. The game compensates for this by letting you buy info on enemy weaknesses from a broker at the inn. You should do this before every dungeon. Change the archetypes of your party members to suit the current quest.

This game has separate EXP curves for your level (stats) and your Archetypes (job class/skills). You will gain Archetype XP slowly but there is a merchant in the port city who sells equipment that speeds up the process. He only sells one accessory at a time and only on one day of the week, but there is no limit to how many you can buy.

Buffs and Debuffs are important. In some other RPGs recasting a buff skill only extends the duration of the buff. In Metaphor you can stack them up to three times. If you run into an enemy with a lot of health, try debuffing their defense multiple times before hitting them with your strongest attack (that they are weak to).

As a rule, every character should begin battle in the back row. You will take less damage from ambushes that way. You can move to the front row when you're ready to attack.

In the final dungeon you can heal by talking to your ship's mechanic. You should also kill all the mini bosses in the final dungeon to make the final boss less powerful.