Explore mutation testing in Ruby applications through this engaging conference talk that uses X-Men themed analogies to explain complex testing concepts. Learn how to transform code systematically to verify test effectiveness, using the `mutant` gem to identify potential weaknesses in test coverage. Dive into practical examples with a sample Ruby application, discovering techniques to achieve comprehensive mutation testing coverage through code simplification and test improvements. Gain valuable insights into Ruby fundamentals, code parsing, test-driven development practices, and clean code principles, while evaluating whether mutation testing is suitable for your specific projects.