The best Dominion offered me was a 'free' access to the cards I paid for for a year. However, Dominion dropped Making Fun and moved to a subscription service where, actually, no, I don't get the cards I paid for. (skip this paragraph if you don't care why) This was because I bought cards with Dominion Online expecting to always have access to them.

I started with Eternium because Making Fun, who previously administered Dominion Online, basically gave me an apology in the form of 17,000 gems. So if you care about having very good rolls on rings and amulets but don’t want to grind, then it’s probably not for you, but the game (like any) is pretty grindy in general so it shouldn’t be a problem if you like it. The third one is a bit more of an issue because crafting (near perfect) jewelry requires gemstones which take a lot of farming. The first two aren’t really an issue: skills unlock over time so eventually you’ll have all of them for free (I don’t think paying players use currency to speed this up much) and xp boosters in the shop only go up 200% so it’s not a huge advantage and won’t affect much unless you’re vying for first place on the leaderboards and those few points from the difference in champion level are all that’s holding you back. The three areas where spending money will give you an edge are unlocking skills, xp, and jewelcrafting. There’s also no artificial mechanism preventing you from playing more like in most mobile games. You can’t actually buy better gear so everyone has to grind for items.

But imo, it’s the best f2p game I’ve encountered or heard of. You should check out the official forum, this subredddit is pretty dead.

Eternium guide reddit