That's a very interesting analysis. A lot of new players started the game and only saw that they could progress in the game renting cards. Renting allows you maybe to make a short time profit but it depends a lot on the rewards that you can generate. By owning the cards you can actually build your deck. If you own an upgraded summoner, you will be able also to play upgraded cards and little by little the quality of your cards will increase. In my opinion that's the way to go. It's what I have been doing for more than 3 years lol
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Thanks for commenting! You make a great point about the summoner and new players could just potentially Dollar cost average small amounts of BCX over time to upgrade them for higher leagues.