How good is the grünfeld defense?

I never knew that you needed approval to move chess pieces?

My last tournament win went like this as most club level games do.

https://www.chess.com/game/live/44598551583

Just wing it since rarely will you get the mainline and never mind an anti-line because you can understand the ideas, themes and strategies to play for.

I accidentally learned the Grunfeld (offline on the app against the engine) on a 3 hour plane ride to Toronto and applied it immediately once I got off the plane.

Or wait until you reach 2400 FIDE…..

Ok

The Grunfeld Defense is a cool opening, but an advanced one for sure. I don't play it for my repertoire with the black pieces, but I do know a good amount about this opening. I don't like to cap ambitions by saying you can't learn something until x-rating, but generally speaking, I wouldn't recommend the Grunfeld to anyone sub-1800 and even sub-2000 I feel like other openings might be more worth playing. If you want to study this opening to get a feel for it or learn some of its ideas, I say go for it! Nothing wrong with learning or even experimenting a bit, but I wouldn't recommend players begin with this opening that early on their chess journey. 

Here are some reasons why I wouldn't recommend this opening to lower rated players:

- This opening is sharp and requires memorizing heavy opening theory; not only is this more work for you, but it also means the opponent is less likely to follow into that theory at the lower levels and this means getting different openings because your opponent doesn't play into this. 

- This opening requires a positional insight and knowledge of endgames most players do not possess. In some Grunfeld lines, black enters an endgame down a pawn...but they are okay! In the Grunfeld, the initiative is sometimes worth more than the material.

- The Grunfeld is known as a "Hypermodern Opening" (or a "Blitz Formation" as Kmoch calls it in Pawn Power In Chess). Hypermodern openings are inherently risky and exponentially so for lower rated players because beginner-intermediate levels are taught to follow chess opening principles https://www.chess.com/blog/KeSetoKaiba/opening-principles-again and one of these basics is controlling the center. Hypermodern openings directly conflict with this to the untrained eye because Hypermodern openings allow the opponent to grab the center (ambitious and risky decision indeed) with the thought that they can prove that center to be more of a target than a strength.

In this exact opening, the Grunfeld Defense, allows white to gain central control (usually pawns on e4, d4 and c3), so that they can then attempt to undermine this center (moves like ...Bg7, ...c5, ...Nc6 etc.) and concepts such as utilizing pawn levers and half-open files. If white can hold central control, then they will probably end up better, but if black can destroy that center, then long-term they will be able to take control of that center and black will have a good game.

Oh one other thing too. If you do decide to study/play the Grunfeld Defense, then the one player you certainly want to study games from is MVL as he is probably the world's leading expert in this opening and he is known for using this opening with black at the top level. https://en.wikipedia.org/wiki/Maxime_Vachier-Lagrave 

@1
"How good is the Grünfeld defense?"
++ Very good, but very hard to play correctly.
Black has to defend accurately as white controls the center.
However, black gets a good endgame.

Hmmmm I think I’ll play some unrated games with it, or attempt to. First without knowing any theory and after with.

Thanks for the insights

I might do that 

Handy app feature?

that can't be good .....castling long with a half open c file.

I think I’m going to take a break from chess, haven’t really been playing it in the first place but still, got to much stuff going on 

I used the grunfeld a lot before dropping it for the budapest lol

This game has nothing to do with the correctness of an opening.

It's a very typical amateur game: Black made a few grave errors, got a totally losing position, and somehow white showed generosity and allowed a quick checkmate after 25....Qe2+ 26.Kg1 Be4.