mate in minimum possible move

two I believe. I kept looking for one but I don't think so. two ways to do it in two, 1.Bf4+ Nxf4 2.Qxf4# or 1.Bf4+ Ke4 or Ke5 because it shields him 2.Bh2# Maybe some others? (edit) the Rxa1 doesn't work in two.

1. Bf4+? Ke4! 2. Bh2+ Ke3 and there's no mate in two.

I'm pretty sure there is a mate in two somewhere because mate in three is obvious and most moves going for mate in two have a single refutation (also stating that this problem is likely to be a composition, not from a game), but I haven't found it.

As a helpmate, it clearly has no helpmate in 1 (equivalent to mate in 1; just check all moves), and there are multiple helpmates in 2 (1. any Nh5-any 2. Qf4#, among others), so the problem is cooked. But if the OP is not skilled, it explains why the problem can be unsound...

It's actually very clever because it's so deceiving. there's always a hole for the king to escape, the squares that would truly pressure the king are always guarded, it's semetrical kind of like geometry. Credit where credit is due is long overdue on this site. In fact it's not coming at all. If we were really interested in chess we wouldn't be in these forums. if this was a bad puzzle you would have solved it with no lingering doubt. it isn't on the puzzle board because of all the people who claimed they solved it when they didn't, and where are they now? He knew what he was doing when he made this. Mark is probably right, three.

look for a way to position at a neutral square before delivering check and maybe that way it can be in two.

there was a good one on a different page that someone left as a joke. the result of the captures left black king with a dark sqare bishop and white king with a knight and light squared bishop. though theres a way to win with knight bishop it can never be when the king with one piece has an opposite colored bishop unless it can be taken away but the lone knight doesn't have the range to do it. Yet it isn't insuficient material so the pattern go's on forever. haha

Alright here's my answer. Bb4 because the queen must remain on the fourth rank for the king to be imobilized. Because the only way to prevent whites dark bishop from moving to Bd6# is to play c5 which never the less results in Rd5# because it's original position was the only thing preventing it. Because whites dark bishop is the only of his pieces not freezing blacks king and so is free to move without checking and letting him escape. Because none of blacks pieces can check whites king on the next move. Because none of blacks pieces can capture a white piece responsible for freezing blacks king. Because no black movement of any kind can effect this. And finally because I never gave up and blamed anyone else. It's simply a mathmatical masterpiece. One of the best puzzles I've ever seen.

1. Bb4 Re4, no mate.

I think it's a mate in 3, for what it's worth.

No look It's so masterful that if Re4 then Qxh5# since this removes the reason for the queen to guard the rank. It's... mezmerizing

1. Bb4 Re4 2. Qxh5+ f5. It's not mate.

Your right. no matter what I do something will get in the way. I don't want to set up the position and find out for sure. It's an illusion meant to baffle any way of doing in two? There's so many ways of doing it in three. How do you just look at something like that and ever really know?

1.Bb4 Re4 (1...Rb2 Qd5#) (1...c5 Rd4#) 2.Rh4#

Here you are then :)

1.Qxh5+ f5 (1... Bf5 2.Qxf5#)  2.Bf4+ Kf6 (2... Ke4 3.Qf3#) 3.Qf7#

I can't for the life of me find a mate in 2.

Black's pieces are defending too many squares for there to be a mate in 2. 

1. Qxh5 f5, no mate in 2.

I plugged this into Houdini a couple weeks back and there is no mate in 2. So there.