Deprecated (Undefined Behavior Book 1)

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Deprecated (Undefined Behavior Book 1)

by C.T. Rook

You don't level by killing—you level by understanding. Understanding costs more. When the System arrives and the world breaks, one survivor learns its rules are code—and code can be read. Book 1 of the Undefined Behavior systems-apocalypse LitRPG series.

Found free on Sunday, October 18, 2026

ASIN: B0HHZRBT6K

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