# Chess Construction Challenge #2-Check!

Xit's time for round two!

Given that:

-Black has 6 pawns and a king

-White ehas three pieces of any kind you to deduce the identity of and a king

Construct:

-A nlegal position in which both sides help to give a legal sequence of 13 mutual checks

Positional ovariations are allowed. To my knowledge, there is really only one way in which this idea can be constructed. I accept alternate answers.

If you ohave questions, feel free to ask in the comments section below!

Good rluck!

There is a slight shortcut for this puzzle if you can figure it out...

• To clarify: W has three pieces of the same kind that we have to identify, or W has three pieces which might all be of different kinds that we have to identify? – Gareth McCaughan Jul 14 at 20:04
• It's the latter option. – Rewan Demontay Jul 14 at 20:09

My position has a fourteenth check too, but that's probably ok. :-)

[FEN "8/8/8/8/8/4K3/2pppppp/RR4Nk w - -"]

These are the moves:

 1. Nh3+  d1=N+
2. Rxd1+ cxd1=N+
3. Rxd1+ e1=R+
4. Rxe1+ f1=N+
5. Rxf1+ g1=B+
6. Rxg1+ hxg1=B+
7. Nf2+  Bxf2+

And here's the whole solution uploaded to Lichess.

EDIT: Looks like 15 is also doable:

The final check feels like such a waste of a piece though; the first fourteen checks are possible with white having only two pieces and a king:

[FEN "8/8/6Q1/8/5R2/5p2/ppp1p1p1/R3K1k1 w - -"]

 1. Qb6+   f2+
2. Kd2+   b1=N+
3. Qxb1+  axb1=N+
4. Rxb1+  c1=B+
5. Rxc1+  e1=B+
6. Rxe1+  f1=N+
7. Rexf1+ gxf1=N+
8. Rxf1+
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