Puzzles needed for tactics trainer

piphilologist
katonas wrote:

Please add your puzzle to this forum topic if :

Each best move is at least +2.5 better than the next best move with the next best move having a value of less than +0.3-1.0 (higher end of this range ok if the main move is very strong)

Examples not allowed :

solution move forced mate, next best move mate in more moves

solution move forced mate, next best move greater than +1.0

So at each step the solution move must be the only winning move (otherwise the problem is 'ambiguous'), or only move to prevent a loss (for example perpetual check or stalemate)

Just wondering if you can edit tactics. just did Tactic# 21279 where the final move a lot of people including me failed because there are several easily winning options on the final move. I know its not the point of this thread but if possible could you could you cut the final move off?

MoonlessNight

Oops! I thought that the best move had to be 1.5 points ahead of the next best move. We were both looking at the same evaluations, but coming away with different ideas. I will make sure that my next tactics fit criteria. thanks for doing this!

theweaponking

theweaponking

That first one up there is an original composition.  This one is a modified position in the end of one of my games where Black wins major material.

To start the puzzle, White first plays 1. Rg1??, and the person goes from there.

 

theweaponking

OKAY - Both of the puzzles I posted are now valid.

Markus24

@theweaponking: Wouldn't 2.Re7 win much faster? (First puzzle)

Anyway, one from one of my games:

theweaponking

Hey, Markus.  2. Re7?? seems like it wins faster, but it seems to run into a cute counterstrike.



EndgameStudent

Markus24, I'll be able to look at your puzzle properly in a few hours. What was white's move before the problem started ? New tactics trainer puzzles must start with the computer moving first.

nate23, perhaps you could test piphilologist's further idea for using your puzzle.

samthechelseafcfan

Hope this puzzle satisfies the requirements for this thread. My sincere apologies if it does not.

EndgameStudent
Unfortunately in puzzle1 weaponking after 2…Kc8 3Re8 (mate in 5) or 3Qa7 (+6) or Re8+ (+5) so there are 3 ways to win and the problem cannot continue. However Markus24’s suggestion has led to a puzzle :
Adding a b pawn for white makes 3…Qf4 the only strong move, and I’ll ask CM Ilmago whether he thinks the problem can be allowed to continue with this move as we usually try to avoid having the most difficult moves at the end of the puzzle as it results in a very low pass rate.
 
When giving the first move for puzzle2 1.Rg1 I need to know the starting square for the rook. I chose 1.Rh1-g1 as this seemed likely. Unfortunately puzzle 2 is ambiguous. 1…Qf3 (+18) and 3….Rxb1+ (+8) and 4….Rxd1+ (+21) is just as strong as 4…Bxd2 and 4…Rf2 (mate in 7) is even stronger. There can only be one winning move at each step of the puzzle.
 
Markus24 unfortunately 1…g6 and 1…Nxc2 are also winning. Please use an engine to exclude alternative winning lines.
 
samthechelseafcfan unfortunately there are many ways to mate in 2 or or more moves so the problem is ambiguous. There must be only 1 way to win for the puzzle to be eligible. 
 
msjenned

http://www.chess.com/livechess/game.html?id=322372595#

 

EndgameStudent

msjenned please ensure there are no alternative winning lines in your puzzles with an engine, such as 1...Rf2+ (+14) instead of 1...Qh3+ (mate in 7)

shoopi

Looks like you need more puzzles!

Here's a brilliant mate in 9 from one of my Marshall Attack games (altered). I have also included variations I find worth adding.

EndgameStudent

shoopi that's a stunning problem. Thankyou so much for posting a perfect diagram that enabled me to effortlessly copy and paste the whole FEN into the analysis and source of

27th puzzle http://www.chess.com/tactics/server.html?id=412215

sidelines

31st puzzle http://www.chess.com/tactics/server.html?id=272083

30th puzzle http://www.chess.com/tactics/server.html?id=202027 

29th puzzle http://www.chess.com/tactics/server.html?id=241405 

28th puzzle http://www.chess.com/tactics/server.html?id=464359 

The potential repetition near the end doesn't make the problem ambiguous because the same mating sequence has to be used to win.

shoopi

Nice variations there.

Indeed, this tactic has high emphasis on square weakness, especially when both sides have bishops of opposite color. It is a useful attacking theme.

Looking forward to submitting more puzzles.

msjenned
katonas wrote:

msjenned please ensure there are no alternative winning lines in your puzzles with an engine, such as 1...Rf2+ (+14) instead of 1...Qh3+ (mate in 7)

between a Rf2 or a mating net w/ Qh3, which is required for a Tactic? Rf2?? You've many other Tactics that had another line but TT picks up best option.

shoopi

Such tactics are NOT ok as far as I understand, and as katonas has said on the first page - "We're gradually deleting ambiguous problems...".

EndgameStudent

msjenned, tactics trainer puzzles with alternative lines with a strong advantage are gradually being deleted.

EndgameStudent

Thanks shoopi, for some reason I didn't see your reply to msjenned until after I'd posted.

msjenned
katonas wrote:

msjenned, tactics trainer puzzles with alternative lines with a strong advantage are gradually being deleted.

Understood on your requirements stated, but personally have yet to see your gradual deleting. I will let you know if I spot those.