Scandinavian in low elo

How useful or reliable is the scandinavian defense in 800-1000?

Depends, do you know how to play it?

Openings are not going to decide games at that level.  That said, the LiChess database has Black scoring ~48% with the Scandi in the U1600 range for rapid and classical time controls.

I usually end up with something like this. C6 is pretty important.

The Scandinavian is fully playable right from beginner up to GM or super-GM level.

After Black plays ...c6 (for instance, after 1. e4 d5 2. exd5 Qxd5 3. Nc3 Qa5 4. d4 Nf6 5. Nf3 c6 we have a Caro-Kann Pawn structure, with the Scandinavian main line continuing 6. Bc4 Bf5 7. 0-0 e6

Compare this structure to a Caro-Kann

Notice the similarity? The Scandinavian (correctly played, of course!) can be looked at as a way of reaching an open Caro-type formation, while bypassing the Panov or the Advance variation.

Boguspawn, sometimes people get bored playing the same opening all the time.

Here's my view on choosing an opening:

At our level... mine as well as yours... our only important task in the opening is to reach an early-middle-game position in which we feel comfortable and confident. Any opening that gets you there is the right opening for you.

Which opening leads to positions in which we feel comfortable and confident?

For me, the Sicilian Najdorf fits the bill.

For you?... Dunno. Try a few different openings and see what you like.

A minor correction (in case anyone is looking at a pawn structures book and trying to find it): the name of the pawn structure is the Caro-Slav (as you can often get to it from a Slav move order as well).

I have been playing the Qd8 variation for a while and It's pretty passive like you're just waiting for your opponent to make a mistake or you just start pushing your queenside pawns up the board and see what happens, and every so often somebody blasts you off the board in under 10 moves. Honestly I think it's bad to play it if you have any kind of ambition.

But he did give up the Dragon after a devastating loss to Karpov in 1974, so it was not that he always stuck to his openings.

I have played many bullet and blitz games against the Scandinavian defense (in classical games I have a 100% win rate against this defense) what I can assure you is that it doesn't matter if you play 3...Qa5 or 3...Qd6 , you will always have the needing to move the queen again, 3...Qd8 is a way to recognize that situation and opt to later move the queen to a convenient place without worrying that the queen is on an unsafe square. Objectively there is no worse move between 3...Qa5 , 3...Qd6 or 3...Qd8 .

The Queen will often end up on c7 eventually, whether you play it to a5, d6 or d8 in the opening.

It's a legitimate defense at any level.

Here's Carlsen (the current World Champion) playing it against fellow Super-Grandmaster, Caruana.

At the time of this game, Carlsen was #1 in the world, and Caruana was #2 in the world.

So the two strongest players in the world, on that day, played a Scandinavian Defense.