Farm Monster Yard for full legendary gear. Best attributes are spell for armour, darkness for accessories, and harvest for weapons.
Continue farming Monster Yard to level up and upgrade your equipment.
Farm Monster Yard to collect and upgrade your Soul Stones.
Complete your Monster Collection for stats.
Make sure all your gear has soul/awakened/enhance. In a pinch you can trade slime coins for the items to do this.
Purchase the sprout pass to get a zeus weapon. If you cannot, visit Hermes to begin trading Golden Laurels. Buy low, sell high. Trade Laurels for a Zeus weapon at Mercury Store.