I've always had a soft spot for MOBA games when I just want to wreck some players up, and league of legends has been a staple go to for 2+ years for me now. However the community has finally driven me out, and I've been playing ARAM customs solely for months now. I've even lost interest in that due to the poison.
Recently started playing World of Tanks. It's a surprisingly detailed and complex moba once you get past the noob stages. But there's no elo system to keep you with noobs while you're learning. As such the learning curve is much rougher and starting out is a pretty harsh existence as you quickly get promoted into matches where you're outgunned and outarmoured most of the time (until about Tier 4, which is about 4-5 days of play for a "hardcore" player).
The games are 5-15 minutes long (for you at least, there are no respawns but you can leave and start a new game as soon as you die), a very refreshing change from the 45-60 minute grinds league could devolve into when it was clear the game was lost by the 20 minute mark. Furthermore, soon as you die you're able to leave and hop into another tank, or you can watch the end of the battle from the vantage of your allies.
It is free to play, but there's definitely some aspects of pay to win. Premium ammo gives a distinct advantage in battle, premium "consumables" do the same. Premium coin can be won in tournaments, but you'll likely need to be firing premium ammo to have any chance at winning those battles. I don't get the general impression that people tend to use these in battle (outside tournaments) other than the odd player, and tactics can definitely make a single player firing premium ammo a relatively small influence on the match.
The game isn't as much an adrenaline game as it is a thinker's one. Calm decisions and knowledge of tank stats are pretty crucial for being a top player. The game reminds me a lot of poker, luck is useful but you really need to know which hands to play. You can get by being a front line brawler, but you'll not survive often. Mind, someone does need to do that job.
Anyway, off visiting relatives so I got time to talk. Otherwise I'd be playing and practicing my Tier 3 arty =<