The easy way to get the "My Favorite Picture" achievement

The easy way to get the most grindy achievement in the game.

Overview

The achievement's trigger condition seems to be quite simple, but it's absurdly random and time consuming to get.
It requires you to get the "Golden Brain" memento perk, it's of extremely low odds of getting it from a polaroid card.
While grinding it, I've found a never discussed before exploit to make it much less random.

My Favorite Picture

I've found out the way to decrease the pool of possible mementos to make it more likely for the "Golden Brain" perk to appear in the choice screen.

There's one memento on every floor. You can get it either from a polaroid photocard, or from a meathole. If you can't find a photocard, it's most likely that a memento has spawned in a meathole.

So, to increase your chances of getting the "Golden Brain" perk you need to do a few things.

Firstly,
choose the easiest difficulty. There was a suggestion that the max difficulty increases the chances of getting rare drops. From my experience of completing the game 15+ times, it's not true at all.

Secondly,
complete the first two floors as usual. Necessarily, take mementos on both of the floors.

Thirdly,
find a memento on the third floor. Most likely, you won't get it on your first try. Be ready to farm it for a few hours. All the people out there suggest you to just restart the level. What you should actually do is to press the "ESC" button and choose the "quit+save" option. It turned out to save all of your weapons and mementos, while still restarting the level. By doing so, you can get more than maximum of three mementos, decreasing the pool of possible perks appearing on the choice screen and making "Golden Brain" more likely to appear in the next run. Repeat it until you find it.

Be very attentive so you don't miss it, it has the longest description of all the perks and the moon is depicted in it.

Conclusion

Thanks for reading the guide, hope it helps you!

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