Anyone play 1. c3 aiming for a reversed london or semi-slav structure?

What are some resources or tips for this unusual opening?

Simply, start with 1.d4.

c2-c3 might, or might not be useful against the particular Black replies.

Exactly! Most of your so-called "Queen Pawn Openings" (i.e. Not the Queen's Gambit), are, in essence, a reversed Defense.

The London is basically a Reversed Slav.

The Colle is basically a Reversed Semi-Slav.

The Torre and Trompowsky aren't really Reversed Versions of any other opening. Can Black play ...d5, ...Nf6, and ...Bg4? Yes, but you don't see it very often.

If you think about it, it should be obvious. Look at the Colle and the Semi-Slav. What does White play in Anti-Meran lines? 5.Bg5. What does Black play in the Anti-Colle? 3...Bf5 or 3...Bg4, developing the Bishop outside the pawn chain. Then the only good move is 4.c4, when after 4...c6, you have transposed to the Slow Slav. If Black plays 3...e6, just like if White plays 5.e3, then you have your Colle as White and your Meran as Black.

There is a book that came out in 2019, The Elshad for White, which is 1.c3, but it is NOT by any stretch a reversed Semi-Slav. White usually follows up with 2.Qa4 and 3.g4 or 3.h3 intending 4.g4.

I played the White side of it maybe half a dozen times, mostly in quicker time controls like G/30 and G/60, but there was a player in Atlanta, Georgia in the fall of 2019 that I noticed moves WAY too fast, and in all of his games, he had used no more than 5 minutes in his first 30 moves. So while I played the Prins Variation of the Sicilian rounds 1 and 2 (1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.f3), and then of course I had Black rounds 3 and 4 (in a King's Indian and London, respectively), I had 3 out of 4, losing the 3rd round in time trouble in a won position, I played this fool that never thought about the position, and I played 1.c3, 2.Qa4, 3.g4, etc, and he was busted by move 30, and only then he starts thinking, but it was too late. For the entire game, he used something like 28 minutes, which was the most of any game and the last 22 or 23 of that was while he was dead lost, and I used somewhere around 90ish minutes.

But it is nothing more than a trick opening. In long time controls, you will typically lose with that opening.

ok thanks for the info guys and for helping out with my curiosity

I wrote a blog on it a while back. Very underrated if you ask me, if you know how to transpose you can get preferred lines in most of these c3 openings like the alapin, torre, london, CK exchange, Colle, etc.. And it also has some unique lines.

It requires some more versatility than just playing the lines straightforwardly but in exchange the lines hit harder.

People who say it is a trick opening are not correct, because it can be played completely legit if you want it to be - it will transpose with good variations in known and widely played lines. It's not my preferred line but so many people already play the London and at that point I don't see why you wouldn't go with this.

Saragossa opening overview - Chess.com

no way ppl actually play 1. c3 i didnt even know ts was a thing