- You start with a few Riot Points. Enough to buy a starter champion, but not much else.
- Riot Points can be purchased.
- Influence points are earned along with experience by playing matches.
- Champions can be purchased with either currency. However, most of them take far more Influence Points, so you can achieve instant gratification through cash outlay or you can play for fun over time and pick up a few more advanced champions.
- Runes can only be purchased with Influence Points. Therefore, you cannot simply drop cash and get the best runes, then have an edge over other players. You earn them by playing. You can earn them faster by getting Influence Point boost periods by paying Riot Points, which of course is cash for acceleration, but not instant gratification since it still encourages you to play and practice the game.
- Every week, there is a free rotation of a set of champions. If you are patient enough, you can try out tons of different champions before spending a dime. If you like one enough to want to keep playing it after it rotates back out, you can drop cash to buy it or spend a giant pile of Influence Points that you've earned. Or, you can simply play with them for fun, endlessly, and enjoy the variety.
- The only "pay to play" thing I've found is that you can purchase extra pages for rune configurations. This can't be earned any other way. It's not overly expensive, it's not mandatory, but it seems like you probably need to do it for any serious competitive play in order to be efficient and prepared for different matches and roles. I wasn't put off by this.
I thought this was a pretty good implementation. I've spent a reasonable, tolerable amount of money so far on the game and have more champions than I probably should have right now, due to enjoying them. The experience felt very much not "pay to win" and that it scaled very well with your interest. The one thing I really liked is that even paying to accelerate your experience was always still contingent on you playing lots of games and therefore getting better and trying out lots of roles and champions. That felt very smart because it doesn't burn you out but invests you further.
If you're researching this kind of model, I would highly suggest trying the game out to get a feel for what the customer experience is like. It seems like a good reference implementation that could be adjusted to match games that aren't based on this champion asset model.