Yup same here, been farming vault non stop. Still haven't gotten the card. Also, out of the people I know doing daily ex roulettes and arks and stuff, no one has gotten those dungeon cards either.

The RNG is really discouraging. And it doesn't even make getting the card any sweeter, when it does drop it would be less a "I worked hard for this" and more of a "finally it's over, what a waste of time" feeling.

I don't know why SE has such a love for RNG. Well, other than to extend content time I guess. I feel like RNG should be used more as a reward for players, than as a punishment locking content. For example, the token system for the current trial is pretty good. You might get good RNG and get your weapon early, but you won't feel dicked if it doesn't drop because you still have your tokens. The tokens gives an anchor so any RNG that causes it to drop before you get it with tokens feels like a discount, and therefore a win. RNG for these cards is just punishment, as no matter how soon you get it, any run where it doesn't drop feels like a complete waste of time.