What was said before by a Mod, was that we open some "boxes", and they stay opened, until we get a certain kind of card (rare, mythical, whatever).
However, the fact is that there seems to be several groups of cards, and I believe their order of rarity is:
a) Trash
- Commons that NO one uses
- Favors
- Low XP Destiny (10, 25)
b) Trash-Uncommon
- Uncommons that No one uses
- Decent XP Destiny (50, 100)
c) Trash-Rare
- Rares no one uses
d) Good-Common:
- Commons that are actually good
e) Good-Uncommon
- Uncommons that are actually good
f) Good-Rare
- Rares that are actually good
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I mean, everyone must've noticed by now that the commons you get are almost always the same crap.
Over and over again.
Even though there are over 1000 Commons, you seem to always get the same 100 - the worst 100.
Just now, it "looked like" I got lucky.
But what really happened, was that I got 2 worthless rares.
It looked like I got lucky, but what really happened, was that I just "spent" whatever rare-drop there was to spend, on trash.
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My theory, is that inside a box, there are 2 different drop types.
The trash = 80%+ and the good = 20%-
So you have a low chance to get a rare, and when you get a rare, you have a high chance it'll suck.
Whatever it is, it surely doesn't make Adventure Mode feel rewarding at all...
And I say this, even though I have decks that win 95% of the time.
I can only imagine the poor players who don't have a sure-win deck to beat bosses, and win 50% or less of the time.
But as you can see the crappy nehant rares drop in the same ratio as the good ones.