- Kill any Monsters.
- End-of-week Salary and Bonus.
- Kill wanted criminals.
- Win at Casino.
- Money Spaces.
- White Loot Spaces.
- Red Loot Spaces.
- Sell your Items, Field Magics, Offensive Magics, Defensive Magics, Weapons, Shields, and Accessories.
- Some Weekly Events.
- Steal it from Adventurers, by them Giving Up, using the Pickpocket spell, Money Trickster, Risque, or killing them.
- Tax Money.
- Gold Bug.
- End of Story Mode Bonus.
- Gold Shoes.
In Dokapon Kingdom and Journey, You can marry Princess Penny if you have the most G, but only if you're playing story mode.
Your on-hand G can be swapped as one of the possible results of the Mix-Up Field Magic.
Also, your G, along with your net worth, is capped at 999,999,999 G. The only way to feasibly get this much money is to casino spam/Hero salary, and then Gold Bug abuse, or Alchemy/Magic Medicine duplication selling.