Mate in 5

You wrote "Mate in 5" but the solution is a mate in 6 moves! Fix that!

thanks for the tip @tempterman, done :)

(II)

Here is an extra-puzzle, Mate in 3. 

Black had just played Qa7-g1, and at first sight this seems to be a very strong move, because now White's Queen will be chased away and can't stop Black's d- and h-pawn from promoting. On top of that Black threatens Qg7 mate, so it seems that White is in great trouble.

However, it's actually Black who gets mated, and Qa7-g1?? was indeed a losing move.

Mate_In_3 -> #3.

(III)

Mate in 4 (#4)

I'll keep on commenting on how the position could have possibly occured in a game (that's what I found amusing about Kurt Richter's way of teaching tactics: Often his comments reminded me of my own careless way of playing, and laughing at blunders which could have happened so easily to oneself is healthy, right?)

'Black didn't fear White's passer, because their bishop controled the d8-square, so he kept on advancing his own passed pawn. However, in chess it's rarely a good idea to underestimate the opponent's chances, here too.'

White to move and mate_in_4 (#4)

Thanks very much, very good puzzles.  Did you make these up or were they published somewhere else? Either way than you very much

Good puzzles. Liked the first one - mate by two knights is always stylish.

@pyramider. They're made up, because sometimes I'm in a mood to program a chess engine (I'm bad, but passionate, at doing this) and then I wanna test the program for bugs or/and time issues with lots of puzzles. So I need to make up a lot of puzzles, and here are some of them, where I think they contain unusual mating patterns (or mating patterns which are well-known, but occur so rarely in a real game that you typically miss them when you shouldn't)

Here is one more puzzle (Mate_In_4; #4)

'Black's knight had just captured a tasty pawn on c3, and Black was already in a mood to celebrate their victory, which seemed to be only a matter of time. After all, he is up a piece and several pawns, so actually Black expected that White was going to resign, soon.

However, in chess it is sometimes dangerous to confuse being up in material with having a technically 'won' position.

Unfortunately for Black with their last move (Nxc3) they slept at the wrong time, because now White can use some 'chess magics' to turn the tables.

(IV) Mate_In_4 (#4)

(V)

Mate_In_3 (#3)

'White had just played 1.Rc1, after all, they are up a piece and some pawns, and winning seemed to be only a matter of time.

Unfortunately 1.Rc1? was a bad move. Why?

(VI)

Mate_In_5

Due to their passer (a2) Black seems to be winning.

Should White resign here, or is there some chess miracle for them, which can save their day?

(VII)

Mate_In_8 (#8) (HARD)

Here a composition where Black is up a queen for a rook, and apparently Black's king is also actively placed and at first glance one would think that it's actually the White king, who is in danger (e.g. they're facing a threat of f3-f2+). How can White deal with this situation? Is there still hope for them?

Mate_In_8 (#8)

(VIII)

Mate_In_5 (#5)

Black followed the principle to simplify the position when you're up in material, so he offered an exchange of Queens (Qc8-b8).

After the exchange he hoped to have an easier time winning, due to his extra piece. However, things didn't turn out as he expected, because now White had an opportunity to turn the tables ...

They're all really nice problems. Some of them I enjoyed quite a bit. You might want to tinker a bit with the first one though since there's a dual on the fourth move (4. Ng3+).

Keep composing.

(IX)

Mate_in_9 (#9)

Here Black couldn't resist the temptation to play Na4+, because they hoped that mating a 'wandering king' was going to be an easy task. Most often it is really a good idea to draw the opponent's king to the center in order to mate him there more easily. Be warned, this game is a paradox exception to this 'rule' ...

(X)

Mate_In_8 (#8, HARD, not even an 'instant' find for some strong programs)

Black hoped that by doubling their rooks on the g-File they would soon be able to promote their passers (h2+h3). Well, what can White do to stop Black's plans? Can two minor pieces really survive the power of two majors? Unfortunately for Black, in some positions the minors can outplay the majors ...

very nice puzzle.

(XI) Mate_in_8

Here White was inspired by hypermodern theories, hence their 'setup'. They're up an rook, and with their last move (Bg2-h3) they hoped to set a tricky trap for Black. Now if Black captures the e4-pawn (Qxe4), White planned to respond Bg2!, pinning & winning the queen.

Apparently this seems to be a 'great' trap, however, sometimes players get caught in their own traps ...

all great and easy mates and easy mate but the best is XI

Just solved # VII - really good fun. Not particularly hard though - once you see the threat of black's queen to e2, it's pretty obvious that each move is check. So just look for the obvious ones.

Having said that, I did stumble at move 6 - I picked the wrong rook check; the one that gives mate in 9 but that's really the only place you can go wrong.

#VIII is fairly straightforward.

#IX is more interesting. The white king staggers up the board like a drunk in order to find a square on which he obstructs neither bishop - I've never seen so many discovered checks in one puzzle (must be some kind of record )!

#X is described as hard but I don't see why; just do what looks most promising. The hardest move must be black's fifth - I defy anyone to have seen that. It's shear desperation but then black's position is horrible !

It just shows that material advantage is nothing if you don't have the position to go with it.

 I found #XI  one of the harder ones - had to search quite a bit for the right moves. But what a strange setup for white - almost totally hemmed in apart from the bishop at b2. That's the main reason why black could pull this off, largely unimpeded 

A really good collection of puzzles, Kullat.  If you post any more, I'll be straight back !