I could argue it has better story telling than the main game...... ok so before I get melted down in the comments, I love and adore GoW 3 and the story and what led to Kratos being like this (though I may add they kinda butchered him just a bit in it) but anyway.
GOD do you get to know a lot about a lot of events in the series as a whole and not just this game only?
I was playing God Of War 3 yesterday with the goal of just f'ing around and not doing anything but having read some of the notes while playing hit me different and made me appreciate the game more than I ever did.
There are the paintings that I of course won't show all but there are definitely stuff u can spend a lot of time analyzing haha. Also Daedalus' workshop and notes do tell a lot about his life.
First thing strongly defends Gaia's claim of her sheltering Zues when he was a kid (In the 2nd image you could see his own drawings, which is kinda cute also awww lol) (I had to grab a screenshot online coz I forgot to take one myself xD.)
"Hades, I beg at your Palace gates, grant me a reprieve!
Have I not become all you have wanted?
Are my debts not paid in full?
How long must I hope for a rescue that will never come?
He becomes a god, while I rot and suffer.
Release me so that I may have my revenge!" For context that's the barbarian king in God Of War 2 who he says also he had to fight his way out to fight Kratos again. It's kind of obvious yes but it also tells you more context about it as if Hades refused to let this guy out and gave him some sort of challenge.
A note scrawled by a tortured soul:
The melody, it plays on and will not stop.
The voice sings of pain and loss. These things I know too well, but still can bear.
It is when the voice sings of hope that I learn true anguish,
a longing for that which I can never have.
There's a good sense of mystery about this one, you never know who this person is and you could have a lot of theories about who this might be and it could work out potentially.
A note written by a young soul:
The fires! The people screaming!
I was so scared. Why didn't father protect us?
The Judges say I have to go now to Elysium and that it will be nice there.
I miss my family.
That's Calliope. It's amazing we also got to see more stuff connecting to chains of olympus and how she went to Elysium.
A note scrawled by a tortured soul:
He was my responsibility.
It was my burden to raise him, teach him right from wrong.
All who get too near him suffer or die.
His wife, his child, his brother, and now me.
I failed him; as a mother, as a human being. His sins are mine to bear.
Punish me for his shortcomings, and grant my son redemption.
It's amazing that we see Kratos' mother still defending her son this hard, like most parents would do.
I left the one for the boat captain out coz it's kinda obvious xD. But that was only in Hades.
But yes. the game does tell you a lot that might make sense or fill the gaps for other games.
Hell it also tells you a lot about poseidon and his obsession with pandora's box and trying to discover it.
I had a fun time replaying the game when my main goal was just f'ing around and I came to realize how awesome it is.