Read up a little more and you'll find the game is some time off being released, so it's non availability on Steam right now is moot as, literally, there is no game anyway.
Right now it's all about crowd funding the game and, for that, you will need some sort of credit (or debit) card. Good luck.
FWIW, I was KS Backer #21 and wanted nothing but the best for this game.
Participating in community and official events could earn you a free Elyrian pledge. Perhaps even a higher tier than that.
If you put the energy in, you could score a pledge without needing a credit card.
But yeah this game is PREALPHA which means its quite some time away from being downloadable. So by then, you might have a good income and a credit card anyway.
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