You are playing the Regex Pattern Matcher game against gpt-4o.

Game history:
Turn 1: gpt-4o proposed text with target items: ["contact-us@domain.com","admin@site.edu.co","user.name@sub-domain.net","2023/10/09","09-10-2023","10.09.2023","&amp;","&#169;","&lt;","&notambiguous;","A-123-B","CD-456-78"]
o3-mini - (low) provided pattern: ^(?:contact-us@domain\.com|admin@site\.edu\.co|user\.name@sub-domain\.net|2023/10/09|09-10-2023|10\.09\.2023|&amp;|&#169;|&lt;|&notambiguous;|A-123-B|CD-456-78)$ (SUCCESS)

Current turn: 2 of 10
You are the PROPOSER.

Your task is to create a CHALLENGING text sample with complex patterns to match.
Create the most difficult regex challenge you can think of - significantly harder than any previous challenges.

Guidelines for creating a DIFFICULT challenge:
1. Use complex patterns that require advanced regex techniques to match.
2. Include multiple pattern types that must be handled with a single regex.
3. Create patterns where naive approaches would either mi... (truncated)