Really cool
I think the visuals of the upgrades could be better, and the gameplay/descriptions, is a little confusing the strategy at certain points.
A thing i think would be really cool, stop all tools at the last 10 items to the player to sort manually, i think it is more dramatic
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I think the letter should be more emotional and more rewarding.
The items were really cool, but they cold also be more emotional.
If you manage to get a soundtrack that fits the emotion on those parts, i think this game has even more potential.
Good game!