A Puzzle: Overwhelmed

1. (For everyone) Which of White's pieces cannot be moved on this turn to a square where it controls more squares than it currently does?

2. (For anyone unrated or rated <= 1200 on chess.com) What's White's best move?

Uh, I misread the question. The King can go to h8!

I see Qd4 checkmate.

This is a common mating pattern... the queen embracing the enemy king while the two squares a knight's move from her are protected by other pieces or pawns.

The rook and the pawn?  Only the rook a pawn is not considered a "piece".

Aye, the rook. Unlike most pieces, a rook controls the same number of squares whether it's in a corner, on the edge, or in the center. A simple but useful truth.

The King can go to h8!

Can you see that on g8, the king controls 5 squares, but on g7 he controls 8 squares, and on h8 he controls 3 squares? Like most pieces, the king is more powerful when he's centralized... although he's also in more danger of being checkmated.

I certainly consider a pawn a piece, so the pawn is one of the white pieces. The pieces consist of officers and pawns. Thus the position has two white pieces that can not move to a square where it controls more squares than it currently does, the rook and the pawn.

Here is documentation on what "pieces" are. The following is from FIDE's handbook of chess, from "Laws of Chess":

http://www.fide.com/official/handbook.asp?level=EE101

QUOTE: 

A white king, usually indicated by the symbol
A white queen, usually indicated by the symbol
Two white rooks, usually indicated by the symbol
Two white bishops, usually indicated by the symbol
Two white knights, usually indicated by the symbol
Eight white pawns, usually indicated by the symbol
A black king, usually indicated by the symbol
A black queen, usually indicated by the symbol
Two black rooks, usually indicated by the symbol
Two black bishops, usually indicated by the symbol
Two black knights, usually indicated by the symbol
Eight black pawns, usually indicated by the symbol

UNQUOTE 

The quote in my former reply is an "authoritative source".

BlueKnightShade,

What else can FIDE say? White starts with 16 thingies and black...etc. They have to use 'pieces' to describe the game to beginners.

When non-beginners talk about chess with one another, they refer to pawns, Kings, and pieces; minor and major.

This pieces and pawns thing is a bit of a stickler. By pure definition every piece on a chessboard, pawns included, are in fact pieces. However, it is common practice within teaching circles to separate the more powerful pieces from their minor foot soldiers. How many of us have learned, or heard the phrase "Develop your pieces"? We all know that teachers of the game are not referring to pawns.

The game is complex enough that it is necessary to break it down in such a way so as to teach a beginner. So yes; we can argue until we are blue in the face that the pawns are pieces, but when teaching and working with puzzles even of this type, the term pieces is mainly used to reference anything that is not a pawn.  

tonightonly7, exactly, what else could FIDE say?

When chess players talk about chess it very much depends on the local way of talking I would say. I think it it usually is clear from the context what a chess player is talking about, so it is no big problem.

Reb, the link you gave applies the word "piece" ambiguously:

First, a quick primer on the relative values of the pieces. These values only have meaning when deciding whether or not to trade pieces. One is not necessarily winning just because one has more material. Having said that, here it is:

     Pawn = 1   Knight = 3    Bishop = 3.25    Rook = 5    Queen = 9

So in above text a pawn is clearly a "piece". Then later on this text appears:

Also, in chess parlance, the Pawn is not considered a "piece" -
Pawns and pieces are usually referred to as separate things.  Knights
and Bishops are considered minor pieces, Rooks and Queens major
pieces. 

***

But as I said above, I think it it usually is clear from the context what a chess player is talking about, so it is usually no big problem. But in a puzzle I would say that the text should be as accurate as possible and in the current puzzle this text was applied "Which of White's pieces ..". That is a written text presented in a forum where people from many countries are reading. The expression "White's pieces" can not be expected to be understood as meaning only officers.