I just bought 100+ Reward cards because they are cheap. So dirt cheap, that I could not resist.
My guess is that the prices will rise long term.
I really believe in this game and I see how many new players join every day.
Just check out this graph. On average there are 15,500+ new players every day.
Some Reward cards like the Twilight Basilisk only have a supply of 30,500 cards.
And the supply decreases because players want to level up their cards.
I think this concept applies to all cards.
More players lead to an increasing ask for cards. Just any card. At the same time we deal with a decreasing supply of every card. This is the perfect combination for higher prices.
More peopl want to play. Which means more people want to buy cards. But the supply just shrinks every day. This is basic economics.
Although all of this is just speculation, no financial advice and for entertainment purposes only. I believe that SL is just getting started.
This game is solid in comparison to many games which are promising but you can't even play them yet. Lot's of hype in the P2E space but not many games offer such a great game experience especially for players who can not invest much money.
You can even make good money here if you only buy the spellbook.
Right now all my cards I own have a value of 323 $ or 5,870 DEC 
Tomorrow I will sit down and make a plan how I can make 500 $ monthly from SL.
I will try to break it down and keep blogging how it is going.
mentalgain
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