This shouldn't be too difficult just run the forest dungeon a few times, farm plenty of gold for the next hero upgrades, take advantage of your teleport (don't worry about the expensive price with an upgraded shop and cash register you should make the money back in no time 100-150k a day) to go back after every floor boss and drop your goods off. Upgrade your weapon and armor also have them enchanted. You also want to stock up on potions I just used the medium potions, the ones that heal for 200. You don't need to worry about the adds for the boss fight just focus on the boss. Also probably good to stop by the town to drop off any goods.