When you first start out, hitting for 10K damage doesn't even seem possible. However, it is in fact doable and quite easy if you have the right setup. I went for both of these achievements together since it saves some time.

Also, I think the description of the Go Big or Go Home achievement may be mistranslated or incomplete. It states "Use the Delusion Fiend's mantra to earn 1,000 gold in one hit". I used her mantra that deals damage but still popped the achievement.

Note: These two achievements are endgame achievements and should not be attempted until you have beaten the main story on normal and hard. This guide also assumes you are familiar with the game and does not explain basic concepts.

There are likely multiple ways to do this, but here's what I found to be an easy method.

1. Head into the Inferno Abyss (endless mode) with the Immortal Sect (obtained from beating the game). A feature of the Immortal Sect is that it allows you to enter frenzy mode in which you deal 1.5x damage and Immortal mode in which you deal 3x damage. Not strictly necessary, but it does help you get this done faster.

2. The first order of business is obtaining the mantra, for which you'll need to visit the shrine (pictured below). By the time I attempted this, I had enough starting gold at the beginning of the run to purchase one right away.









We're looking for the Delusion Fiend's mantra called Big Spender. This mantra deals an attack equivalent to the amount of gold you are carrying. If you don't get it, head back to the title screen and start over.







3. After this, grind gold. I recommended the Immortal sect because the amount of gold you need to get lessens dramatically if you use frenzy or immortal mode to multiply damage. I also got lucky and got a 2x damage buff from the random dragon scale drops, so the amount of gold you need to get can vary greatly.






Be sure to go to the Dango shop at every opportunity to increase your gold and pick up items that help earn gold. One particularly useful one is the item that gives you gold for visiting the hot spring, since you can heal and get gold at the same time.

Note: While our main objective is to maximize gold, you still need to be able to survive long enough to actually use it. Don't be afraid to spend gold at Yutaka's shop for healing or stronger cards if need be. After all, the gold is useless if you aren't strong enough to survive.

4. Once you have enough gold, go into battle and use the mantra to get both achievements at once. If you didnt grind up to 10K, make sure you activate the right buffs/go into the right states to maximize damage. If you mess up, you can always hit F5 right away before the battle ends to head back to the title screen and try again.

Like I said, this is just one of many possible ways to get this achievement. If you did it differently or have advice for people struggling, leave a comment down below to help out others. Good luck and happy hunting.