CommentStreams:4b8770335d1d77c6aaf142c1053a0e7e

Well, here is my observation that might be related to your question. On the other hand it may be totally unrelated.

A few months back before I had my Passion deck all to 10 stars, I was working to get Savage and Inquisitor from from 5* to 6* to 7*, all the way up to 10*. What I noticed was once I got them both to 5*, they started dropping more often during my opening of Silver Boxes during the daily competition to try to place in the top 3. At some point as this was going on and they were both at the same * level. I found that I could anticipate which one would drop next. If I had one more Savage than I did Inquisitor, then 100% of the observed time (at least 80 or 90 straight times) the 1 with one fewer would be the next to drop in a Silver Box. (There may have been 1 or 2 times where both dropped, but there was never a case where only one dropped and it was the one that had the most dupes.) If I had the same number of each one, I believe the next to drop was random, but I am not sure of that.

To take it one step further, after one of the events I found that I had enough dupes of one of the cards to excite it to the next * and did so. Now during the Silver box openings that was the only card of the two that would appear in a Silver Box opening. The other one that I had 80+ dupes of would not drop again in Silver Boxes, until the one I had Excited to the next star level caught up with it. (Even though it was at a higher star level.) Once it caught up then it went back to the way it was before and it would alternate back and forth to keep them at the same level.

Conclusion: There was something in the game that wanted these two cards (both Passion Deck Epic cards) to have pretty much the same number of duplicates at the same time even when at different star levels.

Addendum: Additionally, I currently have only a single Rare (non Main Deck) card at 5 stars or above. (Sentinel at 9*s) Guess what, when opening Silver Boxes I get a drop of 3 Sentinel dupes more than 60% of the time (probably closer to 75% to 80% of the time and possibly as high as 90+% of the time) Then occasionally I will dust them. So, I will run an experiment. I won't dust them any more and see if they quit dropping at an extremely high rate once the dup count catches up to all of my 4*ed non main deck Rare cards.

I do not know if this helps explain what you are observing. But basically, I believe the game tries to keep all of the cards of the same category at the same number of dupes. (Well until they get to 10*s then something else might happen.)