Every day there are activities for double violence or double experience. If you have double experience, you will get a double violence card (a gift bag for logging in, which will be included in the gift bag after a few days of logging in). Double violence will open a double experience card.

Go to the Abyss or the Temple. It's faster, has more experience, and has a lot of explosive things. The volcano port castle is too slow, and it's a waste of time.