user20027: A forced checkmate is a situation in which the player whose turn it is has only legal moves which put the other player in checkmate.
I’m searching for the minimal forced checkmate (the smallest amount of pieces).  If there are several with the same amount of pieces, the one with the most legal moves (which all need to checkmate) wins.
A similar question was asked here, but it wasn’t about a minimal position:
A position in which checkmate is forced (obligatory)

user33434: Here's a reachable position (white to play) with five pieces and six legal moves, all of which checkmate. This was found with the assistance of computer search and some manual input from me.
[Variant "From Position"]
[FEN "5Q2/7k/4p3/5K2/4B3/8/8/8 w - - 0 1"]


20027: <p>A forced checkmate is a situation in which the player whose turn it is has only legal moves which put the other player in checkmate.</p>
<p>I’m searching for the minimal forced checkmate (the smallest amount of pieces).  If there are several with the same amount of pieces, the one with the most legal moves (which all need to checkmate) wins.</p>
<p>A similar question was asked here, but it wasn’t about a minimal position:</p>
<p><a href="https://chess.stackexchange.com/questions/24033/a-position-in-which-checkmate-is-forced-obligatory">A position in which checkmate is forced (obligatory)</a></p>
 33434: <p>Here's a reachable position (white to play) with five pieces and six legal moves, all of which checkmate. This was found with the assistance of computer search and some manual input from me.</p>
<pre><code>[Variant &quot;From Position&quot;]
[FEN &quot;5Q2/7k/4p3/5K2/4B3/8/8/8 w - - 0 1&quot;]
</code></pre>
