As an extension to this question about can a rook and knight without a king stalemate a opposing king, and the traditional minimum-mating-material question, I had a puzzle question:
What are the minimum combinations of material (without a king) required to forcibly mate an opposing king?
R + R/Q is clearly sufficient
R + N + N/B maybe, as an extension from the above stalemate question
On the other hand, there are some sets that fail without a king:
- B(w) + B(b) (but 3 bishops should work, so long as one is on a different color)