sound gambit against 1. d4 as black

It's impossible (playing anything reasonably sound) to reliably force the game into open or sharp territory against 1. d4. You can play 1...Nf6 and play the Budapest against 2. c4 and the c5+Qb6 line against 2. Bf4, but if they play 2. Nf3 or 2. e3 you are out of luck.

You could try for the Blumenfeld Gambit and Benko Gambit. Of course, that's not going to work against the London. I guess you could play the Old Benoni and try to get to those gambits that way.

I looked at your ratings in your profile, you are at the stage where more serious opening preparation is needed, with your opponents starting to know how to correctly reply to various opening schemes that are popular at lower ratings.

But but but I like gambits

I think I’m going to try the stonewall Dutch for d4. It gets some play at the GM level so maybe it will be good for me for awhile. I doubt many 1700-2000 know it well. I pretty much just play the Indian game now, what I’m doing is working for my rating but I’m kind of just sick of those positions at the moment.

I’m going to look into the stonewall Dutch and watch a few videos then try it out. It seems interesting and I’m guessing it’s pretty uncommon. I really don’t like the idea of having my king cracked open but I’ll give it a whirl.

A gambit in the Nimzo Indian. But I'm not sure how (un-)sound it is.

haha just a gambit that isn't trash if the gambit fails. From what I am gathering there really arent any against d4 which annoys me. I'm learning and playing the dutch now and am not a huge fan but its nice to mix it up from indian games , slavs and london systems.

You could go with a Blumenfeld and Nimzo-Dutch repertoire for very aggressive yet still relatively sound gameplay which will usually lay outside of your opponents' theory books.

On chess.com, maybe 1600s may not know a lot of openings well. The knowledge curve starts going up severely after 1600. For in-person over the board ratings...you will run into significant opening preparation around 1400. Someone mentioned the Albin Countergambit...a friend of mine who plays it unpleasantly discovered all the 1300s - 1400s knew the exact and correct responses during an in-person rapid chess tournament.

Not my experience tbh … I beat a NM last week with the smith morra gambit. Not worried about 1300s on here or uscf …. When I play open on the low end I’m something like 90% against them. My last 3 games: wins vs a 2286(French), 2086 (giuco), 1707(Dutch). I’m pretty underrated because I play tons and tons of unrated on here and ranked on lichess. I play solid stuff generally, a few gambits like the smith morra and scotch. But I have over 1100 games in the caro kann and I have pretty much every variation down as black at this point just from playing and analyzing. I just play and analyze right now and it’s working really well. I’ll be 2000 rapid and blitz mid 2025 I guarantee it… I went from 1600-1700 blitz in 1 day last week and went back to unrated playing up.

haven’t studied any openings aside from watching 20 minute Igor Smirnov opening trap videos. I rarely lose in the opening, usually it’s due to just playing too fast which can be a blessing and a curse.

purpose of this post was just some ideas for some weird stuff against d4 and I landed on the Dutch which I’m finding out I actually need to study extensively to be effective… but since it’s offbeat I think it might be worth doing.

Not trying to be cocky or a jerk at all just saying what’s working for me… I will keep doing this till it stops working.

Dutch 1...f5 is fine against 1.d4. You will hear people say it is not sound, but that is rubbish - at least below GN level. I play it with fine results.

Benkö 1...Nf6 2.c4 c5 3.d5 b5 is a sound gambit, but 2.Bf3/2.Nf3 won't allow that.