A skill book recipe is a unique crafting ingredient found in the Big MT, and used in the creation of a skill book at a workbench. There are only thirteen such recipes in game, one corresponding to each character skill. The recipes are one-time use items consumed during crafting, preventing the creation of unlimited skill books.
Inside a footlocker found in one of the small craters. Fast travel to location, head forward through fence, third crater on left with the footlocker, after you fire the artillery cannon at X-7a "Left Field" Artillery Launch.
Hidden inside a vent in the Reception Observation Area of the X-13 stealth testing lab. Go across the center bridge (the one with the toolbox and footlocker at the end). When you reach them look to the left and you will see a rectangular vent which can be opened by jumping toward it and activating it in mid-air. The recipe is inside along with some random loot.
Inside House #00. Sandwiched in a rack of old world scientific equipment on the upstairs landing. Look opposite the table with the toolbox, and it is between the lowest two items of equipment.
A skill book recipe, when combined with 25 blank books and 2 wonderglues, will produce 1 skill book of the type named in the recipe, consuming all ingredients.
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