Openings in bug

Probably the most simple opening to play as black.

knight down is a bit trouble for your partner .

 This opening was pioneered / created by chess.com member croskie: https://www.chess.com/member/croskie

In crazyhouse, I think that the crosky gambit isn't that strong theoretically, but it makes for a good opening in practice, especially in short time controls.

However, in bughouse, I think its value goes up immensely. The pawn on f6 stops so many sacrifices and confers much needed safety to the Black king. As far as equalizing options go, I think it's quite good in that regard...

this is alekhine def but why giving up a knight

ive seen this for years...

You give up the knight for king safety (the pawn on f6 stops Ng5s). In bughouse, with most people generally agreeing that minors = 2 Ps, giving up a knight early on isn't that bad. Arguably, it's quite decent!

There is so much theory around this opening -- and that's saying something for bug... It's been around for quite a long time and for the most part, is considered quite good. It pretty makes an F sac agent black an impossibility. Pawns guard agents bc4, @ne5, and @ng5! -- In addition, it's fairly easy for black to develop and trade. -- White usually doesn't mind their opponent having an additional knight as they have the initiative, and pieces to back up their attack. 

That being said, I have to disagree with ChessMN16 on his last point. Minors absolutely do not equal two pawns -- not Knight anyways. Knights are among the most important pieces in bug. They are worth more than Bishops, Two Pawns, and debatably, Rooks (I tend to lean on the side of Knights being worth slightly more than Rooks, but most people say they are dead even).

Those are the values generally given by most bug players, including the likes of VABORIS.

I don't necessarily agree either. The only way to arrive at the truth here would be to conduct some sort of statistical analysis with perhaps even engine analysis to support the statistical analysis. Barring that, most bug positions are far too situational.

In bughouse quontity beats quality in pieces value. Thats why most of the times i would prefer to have 2 pawns than a knight and 2 minor pieces than a queen in my hand especially in the opening. That's why i personally don't like the so called leaf gambit e4 d5 as black and i never play it. Because its too selfish to lose a pure pawn and it makes big difference at the other board. There is only one way to compensate this - by trading alot more material. If you have a pawn or a piece down it doesn't hurt that much if you have like 5 pieces in hand and your opp has 6 because you can't actually use them all effectively. This way the top players like cheesy and gusmclain who plays this gambit always go for this line - e4 d5, exd e6, bc5 bd7, dxe Qe7, bxd7 Nxd7, Qe2 Qxe6, Qxe6 fxe6. Now your partner is down a pawn but with that many trades it doesn't hurt that much.

On the other hand it's ok to sac a piece for a pawn like e4 nf6, e5 d5. With a pawn in the hand your partner can often recapture the piece back or gain a pawn himself

Hmm...Very nice points you bring up, Sorsi.

Yeah, the thing about the crosky gambit in bughouse is that many times, the extra pawn can just fork two of your opponent's pieces and thus retain some sort of material balance.

While this is a clearly inferior opening, I disagree with Sorsi. Aside from e4 e5, many black openings at the highest level these days (I mean higher than you or I Sorsi, more like Cheesybread / VAB level) involve black sacrificing a pawn for a tempo in order to equalize and have some counter attack. 

If you want the "easiest" opening for black, the one with the most theory is e6 nc6 nf6. While I hate 1. e5, it probably gives the best chances to black overall.

First, why is this "a clearly worse opening?" It's much better than the countless queen sac lines that are played in zh...

Why does e5 give Black the most chances? It's too vitriolic...e5 requires you to be 100% in tune with your opponent. It's too flimsy.

It's clearly inferior because you give up the f6 knight for a pawn, without much by way of compensation. Having a pawn on f6 does not achieve anything of value. Only at lower levels are you concerned about bxf7 type of threats.  Also, 2. ... d5 is bested by 2...ne4 3. qe2 (or qf3) d5 4. exd nxd6 5. d4 d6 is a better line with even material and a +/- position for black with many threats. For these reasons, this opening (which certainly was not pioneered here by the way) has been pretty much abandoned on FICS.

Why does e5 give black the most chances? That is perhaps a slight overstatement on my behalf. I believe it is the opening that keeps the position as equalized as possible while giving the most chances to black. There are certainly gambits which give black good chances as well but e5 gives a good counter-punch. I don't understand what you mean by being 100% in tune with your opponent, but e4 e5 is a game where it comes down to staying on message from a theory standpoint and not being wasteful with your tempos and essentially piece-flow. It is a 50-50 shot in most even matched series. 

And, you mention queen sac openings - in fact there is a queen sac line played by black in bughouse which is actually favored by a player who achieved a rating over 3,000 on FICS.. His handle is Cheesybread. For what it is worth FICS has been the premier chess server for bughouse for the past 20 years. 

Yeah I don't believe in this opening much either, but I'm telling you, it's far better than the countless Q sac lines played (see below). Refuting it isn't an easy task at all.

(It was pioneered by crosky, who's been on FICS for ages. No one said it was pioneered here. Saying that it's "chess.com member croskie" who pioneered it does not mean that he created here or it started here.)

I mean that e4 e5 is very tactical, so you need to communicate very well with your opponent and have him constantly glancing on your board to see that no big threats come up.

I am well aware of cheesybread and countless other strong zh players. I play zh on another site and am not new to this rodeo at all. In fact, I have this to say: Just because a line is played by a strong player, it doesn't mean that that line is objectively sound. This queen sac line, played in zh, is complete and utter BS, but it's been played by the likes of tantheman / JannLee: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. d3 d6 5. Nc3 Nf6 6. O-O O-O 7. Bg5 h6 8. Bh4 Bg4 9. Nd5 Nxd5?? 10. Bxd8 Nxd8

Cheesybread is more than a strong zh player.  He is phenomenal at bughouse. And to be clear, we are talking about bughouse here, not crazyhouse. They are completely different animals. The queen sack line I am talking about is a french exchange line. Not the e4 e5 line you are quoting. I do not condone that line at all.  

OK, fair enough. I was just giving an example of how bad a line some good players play. I've only been bugging with some friends and so only now have I played really strong bug players, so I won't argue with you and will defer to your knowledge concerning that line. Bug is also difficult to analyze as opposed to zh so there's that aspect as well.

what is the best opening to play for black against e4?

There is no best opening. There are three most common responses:

1) To play e5 and get into a 4 knights game with your f8 bishop developed typically to c5

2) To play e6 d5 where the e pawns are exchanged

3) to play nc6 and nf6 first with the idea of d5 challenging the center. There are open lines where white exchanges or closed positions where he pushes the e pawn to e5. This line has a ton of theory behind it and in my experience seems to favor white slightly but as you can imagine, the flow of pieces can affect things quite dramatically.

I think we need an opening explorer for bughouse because there are plenty of more interesting options such as the sicilian defense. Ultimately, your objective should be to find an opening that you can play both with or without pieces.  Your opening goals should be to develop all your minor pieces--this is one of the biggest flaws I see in players <2000 because they are tempted into placing pieces too early. In bughouse, time is paramount. If you are ahead or behind time it makes all the difference so you need to find a line that you can continue with into the middle game without creating significant weaknesses. For this reason, a lot of high level players look to create imbalances with gambits so your pieces are more active.