I want lot of blue crystals
Unfortunately no one will give it to You. You must either get it by your own or buy it. There is no other way. You can make Suggestion thread with request for increasing Blue Crystals around received from LR mines, but nothing else. And no one know if devs will listen to it.
As Cichociemiak stated you only have  choices, either grind it out or out right purchase what you want. I understand the desire to be among those in the forefront for leveling your heroes, but unless you are willing to pay the price, you will have to be patient. Besides there are other means to obtain blue crystals, a number of free events and chests contain them. Now if we were of a mindset as one of our members, we could say, you mean you didn't save any, oh well I have more then enough too bad and so sad for you, we don't need them so you shouldn't either.
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