I've been trying for two hours to make a green card spawn in Chain of memories for a door.
Just a green card. Any number. Two fucking hours.
Edit: Yeah, I'm done. Nothing is worth this suffering.
Uh oh. This is the bane of every gamer's first time with (Re
CoM: lacking cards for the doors you need to open. Because they spawn randomly after every battle, you have little control over what door cards you'll get (unless you're fortunate enough to get a roulette). So you need to learn to conserve your cards so you'll always have one of everything. Only ever use cards of whatever type and number when you have multiples: if you only have one (Blue) Treasure Room card #7...
DON'T USE IT! You'll never know when you'll come to a door that you need to open to progress that will require, among others, a Blue 7 card and
only a Blue 7.
As for the regular doors, their number requirements rise by one of whatever card number you used to create the room: use a #3 card and all room exits will require 4 or higher. Use a 9 and the exits will require a 0 card and only a 0 card.
PROTIP: resist the urge to use a 9 card unless you happen to have a 0 card handy. Fortunately, on any other door you can use the 0 cards to "reset" the number requirements back to 1. So save 'em up.
So to clarify: only use multiples of whatever number cards you have. If you only have one of every number card, use the lowest number you're allowed to. If you follow my advice from the start, you'll likely never need to farm door cards ever in your entire play-through.
As for your immediate problem: Are you far enough in the game to have Roulette Room cards? Enemies in a Roulette Room will always spawn the Roulette card during battle: get it and you'll have a chance at the roulette wheel where you can try to stop the wheel on a specific card. Sometime the wheel will turn slowly, giving you a better chance to claim the card you need.
