Here's a puzzle generated by Sudoku.Coach and posted by u/ddalbabo on Reddit. SC's "Beyond Hell" grids are always a treat, often on the very edge of requiring Forcing Chains.
I've been learning advanced Sudoku tactics for about 2 years now and lately I've been venturing into the world of branched AIC. It's very work-intensive to identify useful examples, but the results are equally rewarding.