user25593: [FEN "8/8/8/8/8/4R3/2N2R2/3N1k1K w - - 0 1"]

Given that this position could be reached in a legal game of chess, and that no piece was captured on the last move, are we seeing the board from White's or Black's side?

user15989: Answer:

 Black's side.

Reasoning:

 For convenience I'll just use white coordinates. If no capture was made last move, the rook cannot come from the f-file, and the black king was the only black piece on the board. Where did the black king come from previously? Not from g1/g2 (next to the white king), not from e2 (impossible double check from both rooks), and not from e1 (impossible double check from e3 rook + c2 knight).


 So the black king must have come from "f2", and the double check from the rook + knight is settled with an unpromotion. Board is from black's perspective; retract -1. Re7 Kc7 -2. dxe8=N and the position unlocks.


25593: <pre><code>[FEN &quot;8/8/8/8/8/4R3/2N2R2/3N1k1K w - - 0 1&quot;]
</code></pre>
<p>Given that this position could be reached in a legal game of chess, and that no piece was captured on the last move, are we seeing the board from White's or Black's side?</p>
 15989: <p>Answer:</p>
<blockquote class="spoiler">
<p> Black's side.</p>
</blockquote>
<p>Reasoning:</p>
<blockquote class="spoiler">
<p> For convenience I'll just use white coordinates. If no capture was made last move, the rook cannot come from the f-file, and the black king was the only black piece on the board. Where did the black king come from previously? Not from g1/g2 (next to the white king), not from e2 (impossible double check from both rooks), and not from e1 (impossible double check from e3 rook + c2 knight).</p>
</blockquote>
<blockquote class="spoiler">
<p> So the black king must have come from &quot;f2&quot;, and the double check from the rook + knight is settled with an unpromotion. Board is from black's perspective; retract -1. Re7 Kc7 -2. dxe8=N and the position unlocks.</p>
</blockquote>
