Dota Underlords

A great example of "simple to learn, hard to master" done right.  It doesn't have the dizzying array of moving parts that Dota has, there are fewer elements dependent on RNG, and obviously reaction time plays a smaller role.  The Dota tie-ins help existing fans of the franchise get started quickly without being inaccessible to newcomers.  Even so, there's still a lot of strategy to learn, with individual hero's abilities interacting with alliances, items, and hero placement in sometimes unexpected ways.  The mixture of luck and skill in matches is very well done, and games themselves give players plenty of opportunities to experience highlights even if they don't end up winning all their matches. 

The overall experience is not very intense, as intense periods of item and hero selection are alternated with the relaxed experience of watching the Autochess-style battle commence.   The whimsical aesthetics actually mesh well with the low-key but still engaging gameplay.  There are very few penalties for abandoning (given that matches can continue without players being engaged) and there's no voice/text chat aside from some preset options, so the relaxed approach to gameplay carries over to interactions between players and the overall community as well.

I was particularly impressed with the amount of single-player content available for around $5, although some of the quests were unexpectedly difficult due to balance changes that have happened since that content was first released.  There's a lot to do even if you want to remain FTP though.  Graphics did not look great on my (admittedly underpowered) laptop, but it doesn't distract from gameplay in any way.  You're going to play this for the gameplay itself rather than the aesthetics or (basically non-existent) story, and on that level it succeeds.  (Although, on this last note, it is funny that White Spire's lore is at least coherent, unlike Dota 2's impossible to understand backstory).

Overall, highly recommended.  Check it out.