When I first started out, the Arena was difficult. Suddenly, I was playing against decks that were well-crafted, fast, and full of nasty tricks and tactics that I'd never seen before when playing against Elders and Half-Bloods. It was a whole new world; one I wanted to explore.
Unfortunately, I was only winning maybe 1/5 of my first matches there, at a cost of 20
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per match - and the one I'd win would only net me 4-10
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reward! So I'd have to continually switch back to my Elder farmer to gain back the funding to go for an elusive Lobotomizer for the RoL/Hope deck I so desperately wanted. It was a frustrating way to gain my education, at first. I'd like it if new players could make some better money, for risking their patience and sanity with no rares and no upgrades.
The reason to scale the earnings is that, once I had a few rares, and some upgrades, Bronze became ridiculously easy, and farming Shards was the new goal. The
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didn't matter - I could just use one of my growing arsenal of FG killers to get some more. I almost felt bad, stomping all the poor little Bronze decks, knowing that some new player's Arena deck was just kicked out of competition. And so, I think it'd be fair for the
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rewards for wins in Bronze to be lowered, either according to your own level, on the number of rares/upgrades in your deck, or by some other metric that allows Bronze to stay mostly a place for newbs to discover and learn some of the possibilities in EtG.