The garden is HUGE, but it gets more and more dangerous the deeper you go. Now that you have the Artorias Crest, you have a nice shortcut to the rest of it.

The foes you face past the Artorias door are not Darkwraiths. Those guys come later and are much worse; what you're fighting is Forest Hunter phantoms. Don't forget, if you're human in Darkroot, you can also be invaded by players who join the Forest Hunter Covenant. Unlike other invasions, there are no restrictions on level for Forest Hunter invasions, meaning you could find yourself facing a level 150 enemy.

You can join the Covenant yourself by talking to the cat lady in the tower, at the far end of the area with the NPC phantoms. I advise against it, though, since once you're a member you can't fight those phantoms without accumulating sin and making yourself a target for spirits of vengeance.

Darkwraiths come in PC and NPC flavors and work basically like Forest Hunters - there's a specific area in the game where PC members of the Dark Sun Covenant will automatically invade you if some other player has indicted you, or if you've accumulated enough sin. Again, you have to be in human form for the invasions to trigger.

The NPC Darkwraiths don't turn up until the very end of the game, by which time they're not much of a threat; however, they're a big part of the fiction.

Steerpike, without giving it away, there’s another way to get deeper into the Garden other than the tomb?

I think so, but honestly I'm not sure what the path is. And I could be wrong about that - if I am, then the Crest of Artorias is necessary to reach everywhere you need to get in the Garden.

It's so easy to get turned around in that place, I never really got my bearings. Even running around to attract the Forest Hunters can be risky. More than once I couldn't find my way back to the stairs!

Two bosses remain in Darkroot after the Moonlight Butterfly; one's optional and one's not.

There is an illusory wall in Darkroot Basin, too, that provides another bonfire and a shortcut to the Valley of the Drakes. It's interesting to see how the whole world fits together.

It's funny Botch, I'm in NG+ right now and Capra Demon is absolutely destroying me. I can't get past him, there's just no room to maneuver! It's driving me crazy since comparatively speaking, Capra Demon's not really a very imposing boss, especially compared with some of the things you're about to face.

You guys must be really good at this game, because I never had anything near 25 loose humanity. 2, 3, maybe 4; that was about it. In fact I only ever cracked the stuff in the clay vessels if I was planning to summon help. If you spend enough time roaming the Depths, you can collect a pretty good amount of the storable kind from the rats.

Pokey: nicely done on Gaping Dragon. Defeating that thing was a kind of turning point for me, a point where I sort of stopped believing I had no chance of finishing and started believing that it could be done. Blighttown is... horrid, awful, the worst; but it too is a turning point of sorts.

xtal, you're flyin'. Enjoy Anor Londo - it's kind of a treat from the developers after all the horrors of the Depths and Blighttown and Sen's Fortress. It marks the halfway point in your journey, too.

There is a lot of hidden stuff in Anor Londo - an entire hidden world, plus a very significant amount of plot material that may or may not be exposed depending on how you behave and what you find while you're there. It's during your time in Anor Londo that you realize Dark Souls actually has an immense and comprehensive backstory and supporting fiction, but From doesn't tell you what much of it is. Not because it doesn't exist, but because Dark Souls doesn't make anything easy. Your imagination, and your own conclusions, are necessary to find your own story in the game.