You are playing the Regex Pattern Matcher game against claude 3.5 sonnet.

Game history:
Turn 1: claude 3.5 sonnet proposed text with target items: ["2023/12/31 15:45:30 UTC","31-12-2023 15:45 GMT","12.31.23 3:45PM EST","XX-1234-Y-789","XX-5678-Y-101","XX-9012-N-111","192.168.1.1","10.0.0.0","172.16.254.1","https://example.com/path?q=1","sftp://server.net:22/file","https://valid-site.com/path#fragment"]
Mistral Nemo (12B) provided pattern: solve (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... (truncated)