You are playing the Regex Pattern Matcher game against o3-mini - (low).

Game history:
Turn 1: o3-mini - (low) proposed text with target items: ["john.doe@example.com","test.user+filter@sub-domain.example.co.uk","+1 (555) 123-4567","0044-207-946-0123","(123)4567890","2021-12-31","31/12/2021","12.31.2021"]
o1 - (low) provided pattern: (john\.doe@example\.com|test\.user\+filter@sub\-domain\.example\.co\.uk|\+1 \(555\) 123\-4567|0044-207-946-0123|\(123\)4567890|2021-12-31|31/12/2021|12\.31\.2021) (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 ... (truncated)