Graves is unlike other ranged carries. He can take a licking like a man. Ha.
Why not capitalize on this aspect like the American banking industry?

I'm not one with words, so I'll be updating this guide consequently based on response.

This particular build is mildly like a Tanky Teemo build, but will let you burst down enemies efficiently with his Q and R.

Let's hit the trail then, yes?

Graves benefits a lot from most masteries in the offense tier save for CDR amd and he deals inconsequential magic damage with w so Archaic Knowledge is right out of there of course.

You could also take a point right out of Sorcery for Offensive mastery for mildly easier farming but you really shouldn't have too much problems farming with Graves. A quick Q -> W mixed with auto attacks and you can clear a wave fairly easily. Although don't spam that, his mana pool is unforgiving.

You can switch Resistance and Hardiness as you see fit based on our rune selection, also if you choose to get some Dodge Seals, that could help stacking with Evasion. I don't like to do that with Graves though as he can dodge skill shots fairly easily with his E to avoid a trap and smack, and you should be able to control your distance from an enemy with Graves without too much difficulty.

ArPen Quints and marks will ensure your Q and R at 6 deal maximum damage early game, when your dominance can begin. Other decent choices are flat damage or a mix of ad marks and as quints if you want to be an auto attack hero.

Health Seals give you a minor boost for an Atma's and makes you a tad beefier to play more aggresively in the beginning. You could easily switch these for Armor or Dodge depending on the opponent or your playstyle.

Mres Glyphs seem like the only logical choice left to beef up a little. Other decent choices are CDR for everything but Grave's E, or mp5s.

Exhaust is a good choice. A good E with Exhaust can pretty much sign someone's death certificate.

Ignite is also good to stop heals from nullifying your burst or making sure that Ezreal doesn't flitter away with a sliver of health.

Other good choices are Cleanse or Ghost.

Start off with a point in E to gap close and dodge skill shots as well as a surprising amount of damage if you time it right at level 1. You want First Blood.

Follow Q to rank 3 after that with a point in W at 4 and R at 6, then alternate E and Q rank ups, maxing Q first then E, as around this time you'll need to mix up both auto attack and skill usage to take down a foe.

Now to the nitty gritty.
CORE:
Start off with a Doran's Blade to give your hits a tad more oomph.
or
Start off with Boots of Speed and some Health Pots if you need to dodge skillshots/expect danger, you know, the basics.

Keep in mind that if you plan on a Randuin's, or think you might have a tough time farming, a Philosopher's Stone is not out of the question at this point.

Second visit if you need more tankiness, another Doran's isn't too bad a choice, but my usual main priority is an early Phage, so pick up either of its components if you can't get the Phage just yet.

Next priority is boots. Easy here, pick situationally. Zerkers for if it's going smoothly, Mercs if there's heavy magic damage and CC heading your way, and Ninja Tabi isn't too bad if there's AD on your tail and you got dodge runes.

After that, BF SWORD time. Build that mother fan into a Bloodthirster ASAP, then get your Frozen Mallet.

If you're feeling underfarmed or getting taken down, Wriggle's is a great alternative for now. Hexdrinker also can be a good choice if you're having AP woes.

Your next goal is Atma's. At this point you should have you Boots, Your Bloodthirster, Your Mallet, and an Atma's, possibly a Wriggle's/Hexdrinker as well. If the game is still dragging on after this, there's some luxury items to consider.

Tankier Items
Randuin's - Some extra AD from Health, can slow down those pesky AA Heroes.
Banshee's Veil - Some extra AD from health + mana. If Karthus is picking on you or something.
Thornmail - A big finger to AA Heroes.
Warmog's - If you have the cash, why not? I don't get it early cuz it cuts your burst down something fierce when you should be dominating.

Curbstomping Items
Infinity Edge - Do i need to explain why?
Last whisper - If you've scared them into thornmailing or something.
Bloodthirster - Yes. Another. See the terror envelop and well out from their eyes in the form of tears.

Situational Items/Other Items
Cloak and Dagger - Not a bad item if you want to swap bloodthirster for IE early game and still want tenacity if you got Zerker's or Tabi. You can always sell it later.
Hexdrinker - For AP woes.
Wriggles - For cash flow woes/ad woes.
Phantom Dancer - I don't particularly like Phantom Dancer on Graves as his E is a free one, and his abilities early game are what's melting people's faces, but you could if you wanted to.
Trinity Force - If you think you can afford it, and don't need to be too tanky you can always build this from your Phage instead of Frozen Mallet.
Stark's Fervor - To benefit more from Lifesteal and you have champs on your team that can also benefit from it.

Like I said, I will be updating this guide based on suggestions/comments and once I play Graves a ton more considering he's my favorite champ nowadays.

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