In no way does it have a mechanical or flavor tie to the Rakdos Guild
It makes sure your deck is consistent and complete, helping identify what your deck might currently be lacking, letting you refine your deck lists independent of playtesting
If it leaves the graveyard before that point, it will stay in whatever zone it's in, even if it's returned to the graveyard before the ability resolves
This means that it is at least somewhat difficult to deal with for your opponent at parity or only a slight loss and especially not at a gain
Here she starts with a lower loyalty but she can +1 a fat 3/3 as soon as she arrives with a cool counter and she can -2 on arrival (or later) to net a free creature from your library each time you cast a creature
This will start by doubling the number of dice you are rolling each time, helping you achieve that higher dice result and therefore better value out of each dice rolling cards abilities