A way to really make it worth grinding the achievements would be for achievements would be to use them to boost the impact of bonuses. For instance if every achievement gained for the click bonus made the click bonus stronger (for instance if after the first time you got the achievement the bonus gained a .25 additional effectiveness), that'd definitely make it worth spending gems on the purchasing the bonuses that increase the amount of time the bonuses last. Just a thought.
I LOVE this game, you guys did incredible.
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Thank you very much! Glad you enjoyed it. :D