Rechargeable brick-sized power cells (and their fabricator) that Carl uses to run the battery-powered interdiction carts.
Dwarven batteries are brick-sized rechargeable power cells common across the crawls, powering devices like the interdiction carts on The Iron Tangle. Carl acquired a battery fabricator early — trading his Louis L'Amour books and a jug of moonshine to an eager moleman shopkeeper, suspecting (from the cookbook's power-supply section) its odd placement wasn't chance. The fabricator came with fifty batteries; each takes four full mana potions and five minutes to fully charge, then lasts a very long time, giving Carl about a dozen usable cells.
The carts at station 75 each hold one-to-three of these, so Carl strips the depleted ones to swell his stash for the rescue.
A brick-sized dwarven battery cell; the fabricator a device that charges them from mana potions.
Carl's portable power supply for running the battery-driven rescue carts off the dead lines.
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