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That's BS, because black should check with a queen or a rook. Not a true mate in two.

Yep, I see now that tricky bishop doing its job  

najo2, you missed the 2Bh3++
The Ra8 is important..

1. ... Nc3
2. a1=Q Ba6#
or
1. ... Nc3
2. h1=Q+ Bh3#
either way it doesnt matter

But on each one it is mate in 2.
If black checks with a Queen, white just blocks it with the Bishop and ... Mate

@afoot2

1. Nc6 g1=Q
2. Bg4#

Again the Bishop blocks the new Queen and Black has no possibility to save his King.

Black's pawn at d2 is very important also. It keeps Black from checking White's King with c2-c1 =Q +.

How can black stop mate in 2 after this move?

1. ... h1=Q+
2. Bh3#

1. ... Kg8
2. Be6#

@bobandyo

Thank you! Missed that one.

There's definitely more to the eye than appears at first.

Yes indeed...

(1) White needs to get both N and B out of the way.

(2) The N must move first, in case Black decides to move 1... Kg8, allowing 2. Be6++ (checking through f7 and preventing escape from the back rank).

(3) After the White N move, if Black does NOT move his king (because of 2. Be6++), he must promote a pawn, after which a White B move is discovered check. Therefore Black's promotion must be to a Q or R (which is also the only way to check the White king, if it is the h-pawn that promotes), since a B could not escape from the promotion square (being blocked in) and a N not move far enough.

(4) For this discovered check to be mate, Black must be prevented from interposing his newly promoted Q or R on the back rank, or capturing White's R - even if it promotes with check as the h-pawn would. The B, of course, can move (when discovering check) to intercept on any file - including intercepting a Black check on the h-file - with one exception: it cannot move and block the c-file, so the block on that file must be made on White's first move by his N, therefore 1. Nc6! is the key.

Loved it  
Very clever.
Nice setup