Epic Cards Battle

This is a question for VIP 3+ players - what is the algorithm for refunding rubies?

I had a look at a few cards and they range from costing 2.6 to 15 gold per ruby. I want to know how to optimise my refunds - any tips ECB or other VIP 3+ players?

See Pr0digy answer below. (edited for clarity)

Sacrificing multiple cards in one time is more efficient than sacrificing one by one. Hope it clarifies.

I believe the original poster was asking for refunding rubies, despite how many cards you own. If you have a level 40 silver card, it costs 8,000 to reset to level 1, but a level 20 silver card cost a quarter of that. I think the OP was wondering if there was a formula for why this is. You'll get 1,953 rubies for refunding the 40 silver card for 8,000 gold, or roughly 4.1 gold per ruby. The level 20 card you get 198 rubies for the cost of 2,000 gold, or roughly 10.1 gold per ruby.

My level 28 epic card would cost me 23,120 gold to get back 19,137 rubies, or about 1.2 gold per ruby.

It appears that the more rubies you get back by resetting the level, the more efficient the pricing gets. I wonder if you could build an algorithm based on the numbers above and maybe a few more examples from what you own.

Is that what you were asking, Ironbunt?

Thanks Pr0digy, you hit the spot! ECB can you please tell us what the formula is to save me spending hours trying to revise high school mathematics?

So yes to clarify I'm talking about refunding rubies, which is only available for VIP 3+ players.

Cheers!

The cost is (X^2)*5. X depends on cards' level and rarity.
Basically, the cost for reset high level card is more efficient than low level card.

Very nice, thank you ECB admin!