Not all parts of the player’s machines are vulnerable to attacks. The 
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Fridge’s weak spot is its 
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red crystal
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 while the Fish’s Achilles' heel is the 
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green crystal.
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Money
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 can be used to upgrade the machines after every mission. There 
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are three kinds of upgrades.
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 Shield Upgrade
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 improves endurance and 
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Fridge’s HP regeneration rate.
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 Energy Upgrade
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 enlarges Energy’s pool 
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and speeds up Energy recovery. 
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Speed Upgrade
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 allows player to move 
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faster.
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Only one Guardian can be on the screen at the same time.
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