I feel that the card upgrade using ascension gems would be more useful if it didn't count as a normal card upgrade. So instead of for example upgrading a card to level 4, you upgrade it to 3+1 with the same production as a lvl 4, but upgrade number of cards is still 1000 (for lvl4 and not 10000 for lvl5)
Not even on the 3rd realm yet, so please correct me if I'm wrong. I think the biggest problem with this game is keeping interest. There is not a lot of motivation to keep changing formations once you've got a realm setup figured out. One way I suggest changing it is to remove cards in the layout used when you ascend and then also to maybe pick packs by stars instead of just 2 tiers, which will create a more sloped progression each ascension. Obviously there needs to be more to ascending in general as well. Another way to create more formation experimentation is to have more specific accomplishments and these would also then have some sort of useful reward. Maybe even add a cross realm element to some cards where a certain number of one card in a realm boost the performance of another in a 2nd realm
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