I just looked at the Coin Dungeons and am a little shocked at how expensive the most expensive ones are. Secondly, I know that some players have 999,999,999+ coins. I'm familiar with Weekend Dungeon (and I won't say more about it to be answered), but I feel like there is at least one comparable alternative. I recall mention of Gold Dragons.
How do I make bank?
Best Answer
The best way is the weekend dungeon.
Find a friend who has Ganesha and bust out your best team to take on weekend dungeon master. You can easily squeeze 400K coins in a run.
I would not sell metal dragons for gold, even though they are good payout, as they are better EXP food.