This is another "Mining is too long comment"
But let me explain why.
Before we could break a block with 10 hits in 20 minutes (for energy recharge).
20 x 16 blocks = 5h20 minutes for deeper levels and better rewards.
Now it's 15 minutes for 1 energy.
15 x 10 = 2h30 for one block
2h30 x 16 = 40 hours.
It's about 8 times slower
So yes the games is slower for going to deeper levels.
Instead of making reward x10 it would be better if blocks can be broken in 1 hits (10 times faster again)
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