Bughouse for Beginners: Survey of Opening Theory for Black...
Preliminary Remarks on Chess and Bughouse Theory
Much of chess opening theory goes out of the window in bughouse. Some of the most common chess openings are just not feasible, or barely feasible, in bughouse. The Sicilian defense is at best experimental and unreliable.
The Caro-Kann defense is pretty much untenable. Tried and true openings like the Queen's Gambit and The Nimzo-Indian never arise, because they are based on early c pawn moves by White, which strong bughouse players know better than to make.
The Ruy Lopez is greatly inferior to the Italian Game, because the White light squared Bishop is more useful when directed against the f7 square than against Black's c6 Knight. In the Ruy Lopez, the light squared Bishop exerts long term pressure on Black by threatening to undermine Black's control of the e5 pawn. But this is just too slow a procedure in bughouse.
Some openings are tweaked, like the French Defense. Some openings which are disadvantageous in chess are more viable in bughouse. Openings which are considered cramped in chess are better in bughouse because they are less susceptible to certain piece drops. The St. George Defense is considered slow in chess, but it plays a Sicilian Defense-like role in bughouse.
This is a quick, pragmatic guide to getting good bughouse games as Black. By 'good', I just mean not getting checkmated or losing a lot of material by move 9. I will give responses to 1.e4, to 1.d4, and then offer some ways around some annoying move order tricks. I will give the most essential details, and not much more. But this should be enough to help you avoid getting horrible positions. The most important thing to know about the openings in bughouse is when opening theory from chess is inadequate, and why.
Dealing with 1.e4
The French Defense is a most flexible and reliable way to deal with 1.e4. You get to break the symmetry immediately, and adopt a waiting strategy which may culminate in some nice attacks.
At the <2000 level, you will often encounter the Advance Variation. In this variation, most important difference in chess and in bughouse is that in bughouse, you don't play an early ...c5.
A strong chess player might worry that Black's position will be cramped. In chess, it very well might be. But in bughouse, it isn't cramped. It's just solid.
If you're being positionally squeezed, you can often just sacrifice the Queen and start attacking on e3.
The pawn drop at e3 is often overwhelming, and well worth the Queen.
White can also exchange the pawns. The key thing to know in the variation is that you can make good use of ...c5.
Black can be sort of self-sufficient for a while here, while feeding their partner.
White can also play 3.Nc3.
An honorable fourth mention is if White does not play d4.
