I'm creating an extremely difficult challenge requiring complex pattern matching across multiple formats. This challenge includes advanced email formats with plus signs and hyphens, mixed-format phone numbers (with country codes, spaces, dashes, parentheses and optional extensions), dates in different delimiter formats (ISO with hyphens and European style with slashes), and serial IDs that require backreferences to ensure consistency. Additionally, decoy entries that appear similar but are inval... (truncated)