Review.
"Once you reach Level 30 while holding a Heroic Guardian Pass, every level you earn after that will get you a Guardian Chest. Guardian Chests include valuable Resources and other extra Rewards. You can get an unlimited number of Chests this way, as long as you keep earning levels. "
Yes. 10% chance, every three chests received, to get a level V skill stone is "valuable". The rest of the rewards are not.
Its a shame the amount of attacks needed for "unlimited" chests increase exponentially, compared to level 1-30. Prepare for 1000s of attacks for your "unlimited" chests, with very doubtful value.
Not presenting the amount of energy expenditure needed, when selling, is bad business practice. (I dont want to use the word "scam" here from a legal perspective, but it would be approprate from an ethic and morale viewpoint).
Well, I am not surprised in the least. In conclusion you get some value for your 1-30 rewards, free high level guardians for faster levelling primarily. Its not a bad package from a pay-to-win perspective I suppose, vaguely worded and marketed. But for me personally not great value, since most rewards are usless or already in more supply than needed.