The Vienna Gambit

I've been playing chess for over three years and have a US Chess rating. However, it’s always been challenging to find a solid opening that reliably counters White's common 1. e4 move, given the vast number of responses available. Can anyone offer some guidance?

A trap against e4: g5, d4, g4, Qxg4, d5, Exd5?? shows the guilt of greed after Bxg4! And you win the endgame.

I play c5 but I won't recount all the reasons why here, if you want my advice on what to play there as black I wrote a blog on it - A Tour of the Sicilian - Choosing a Variation as Black - Chess.com

In general c5 can be played in many different styles, and it's more positional than e5 i.e. you don't run into whites landmines to the same extent.

If I were going to play e4/e5 I'd play the petrov without hesitation after 2. Nf3.

Against the Vienna I'd also play Nf6. If you know the Vienna gambit lines there are some early Qh4+ queen trades that simplify the game and give black a small edge. At least against the Qf3 line, I'm not entirely sure about the Nf3 line. But generally I think if you just know your lines you'll do fine against the vienna gambit, I'm a vienna player but I don't play the vienna gambit in an e4/e5 context, only in a Van Geet context, since it has a more formulaic response for black.

Against the Vienna w/ Bc4 I'd just recommend the Frankenstein-Dracula. Again it's a sharp line but if you know it ... it's going to be very drawish for white. As an e4/e5 player I don't think you can really avoid memorizing continuations but if you can at least avoid exponential increase in the size / number of the lines by entering more forcing variations... I think this is good for you.

And against g3 in the vienna I'd just play the immediate d5. This will be a more positional game, probably it's the best play for white in an e4/e5 context here, but it's technically equal, just a game of chess really.

Overall Nf6 vs. the Vienna allows you to play more forcing lines which don't grow as much in size complexity, and I don't think the vienna gambit is even worth being afraid of if you're prepared.

Against the four knights italian the spanish mirror and the rubinstein are both good. Spanish mirror is easier to remember, rubinstein is sharper but I think gives black better chances. You'll run into the four knights more often as a petrov player so you could consider investing more time here and learning the Rubinstein, but it's up to you, if you want something very easy just play the double spanish.

Against the Bishops opening... you already face some of these lines via the Petrov, but again play Nf6 and followup with c6, you avoid the italian this way.

For an amateur player I think it's very important to avoid your opponents lines and take them into yours where possible... this is even more true in e4/e5 which is so full of sharp tactical continuations. And you really don't have time to memorize everything. There are ways of taking the initiative as black against the Ruy Lopez - jaenisch gambit or the fiancetto defense... I actually prefer the fiancetto. And against the scotch... honestly the scotch isn't great, just learn the schmidt variation, very forcing lines where black is doing very well. But the italian poses a real problem, it's so incredibly non-linear and full of landmines, deep forcing continuations where black is in danger, and so fourth... you *could* just really buckle down and study the italian... it makes more sense to do that if you also play the white side of the italian. You could also try avoiding it via the paris defense, which is actually pretty underestimated, there are some very interesting lines there. But still I think the italian poses a major problem and so I prefer the petrov.