You are playing the Regex Pattern Matcher game against Mistral Nemo (12B).

Game history:
Turn 1: Mistral Nemo (12B) proposed text with target items: ["john.doe@example.com","jane_smith@company.co.uk","user123@domain-name.info"]
Gemini Flash 2.0 provided pattern: john\.doe@example\.com, jane_smith@company\.co\.uk, and user123@domain-name\.info (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 miss matches or match too many items.
4. ADVANCED PATTERNS to consider:
   - Mixed formats (emails, phone numbers, dates with different separators)
   - ... (truncated)