I play a lot of digital card games. When I was working on Runescape Chronicle, I played that, as well as Hearthstone, Duelyst, Faeria, Magic Duels, Elder Scrolls Legends, Infinity Wars, Gwent, Solforge and, most recently, Eternal. Recently, from a professional point of view, I’ve been fascinated with the different ways that these games run their free to play economies.
Hearthstone, of course, set the benchmark for generosity and card acquisition rate. It’s interesting to see the different ways that these games approach the problem of getting cards and currency to the player. Some run a similar setup to Hearthstone (Elder Scrolls), whereas games like Eternal are trying to innovate (offering players a mode where they draft cards, then keep all cards they draft).
One thing that strikes me is that, in general, these delivery mechanics seem focussed on the velocity with which players earn cards, rather than creating the core retention loops seen in games such as Clash Royale. I know that this was something we came up against when working on Runescape Chronicle. We had a very clear picture of card acquisition rates, but ended up leaning on Daily Login bonuses as a means of encouraging players back.