U-Invent machine

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A U-Invent machine and its menu.

U-Invent machines allow the player to invent advanced (and very powerful) ammunition and tonics, as well as automatic hack tools (particularly useful for those who prefer to direct their tonic choices to other categories). Using various items found around Rapture (rubber hoses, alcohol, brass tubes, etc), the player can make save money and build useful tools for battle.

The Prolific Inventor Engineering Tonic makes inventing especially useful, as it doubles the amount of ammo received.