Grand Chase Dimensional Chaser/Farm Prana

Sell Heroes
Selling 6☆ S and A rank heroes on Friday for a 10% chance of gaining 2x prana and prestige marks is the most efficient method of gaining prana.
 * Upgrading B rank heroes is not recommended because of high Monster Card and Evostone usage with little return.
 * Fusing 5☆ +9 Heroes is recommended to minimize Evostone usage.
 * Do note that the amount of upgrades don't contribute to the prestige mark or prana sold.
 * Fusing A+S 5☆ +9 Heroes During Hot Time is also a viable option. Chance of getting an S hero is about 50%-60%. The percentage is derived from personal testing of 12 total fusions. (Requires more testing)

You can increase the amount of prana and prestige marks by awakening B and A rank heroes. Though this does require more resources, if you're desperate to make every hero count you can use this method. Do note that it's still best to fuse to B rank heroes after you've gone through S and A ranks if you so desire.

Wizard Labyrinth
Priority should be Do note that even though you're marking Prana, that this Wizard Labyrinth doesn't supply enough of it to make it profitable. You're better off investing in units to sell.
 * 1) S Rank Hero
 * 2) Monster Card
 * 3) Gold
 * 4) Prana

Request Coin Shop
Don't buy prestige marks this way, it's a waste of resources, you're better off buying the monster cards.