Talking about upgrades, the game is sorta grindy since the weapon upgrades increase the power linearly, which makes the upgrades in late-game very insignificant. And the cost just increases too much for every level, which makes the 200 dollar bonus in wheel spinning totally unhelpful.
And about weapon, a maxed pistol is still too weak in late-game, maybe it is intentional. But taking the spike gun is an instant suicide. Its DPS is far too low comparing to other weapons in same level, not even talking about how slow its bullets move, making most of them miss. I enjoy the crossbow very much though.
Auto-aiming is not a big problem. And auto-aiming enemies out of the screen is also not a problem. But what's the point of it when the bullets can't hurt the enemies out of screen? Everytime I see this, I shout "it's a trap" in my mind.
Last but not least, wish I could upgrade the items in shop. Many of the items really have potential to be upgraded.
I cannot achieved Master of Alchemy forever. I have finished finding all the elements and now all the reactions are restricted. Even water + fire cannot create alcohol. This happened to all the episodes.
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Try to reset the second episode and make all reactions with Ph. Stone carefully