The gameplay is fun, with a good amount of team compositions you can compose. However, there is a grind after a certain point where you try to get the best cards (characters, equipment, etc.) through card packs which are just loot crates. While it does take time to get these, it is not impossible. Paying does make it easier, (as with nearly all free to play games) but it is far from necessary. I think it's a good game that some people dislike due to their misunderstanding of it's mechanics.