I am not a ranked Yorick player in any way - just a casual normal player, but I have played several successful games with him enough to believe that this is an excellent build for a normal game.

Yorick is a slightly tanky mage turned late game dps. He's in a very odd category of his own - but doesn't fail to deliver.

Pros:
Although melee, has long range skills.
Can lane infinitely long depending on his mana.
Long Range harass - strong zone controll
Heals very fast using his Omen of Famine
His speed is boosted very well with Omen of War
He can start teamfights 6v5 using Omen of Death
He can revive teammates for 10 seconds
Farms easily after obtaining his Sheen

Cons:
Using Omen of War to harass is very weak.
His ghouls do nothing unless you have many of them.
His ghouls glitch easily and won't attack.
His ghouls are susceptible to junglers and many champions who can recover health off of them (I.E, Nunu & Willump)
His Slow, Omen of Pestilence is horrible.
His scaling is mediocre.
His Skills have low base damage - he needs to spam them as much as possible.
Very dependent on early blue buff, and dependent throughout mid-game.

greater mark of desolation
I use this on all three builds for a reason - it's the only rune you should be using. Marks are significantly better for offensive stats, and of which, armor penetration benefits him the most. Alternate runes that can be used are Magic Penetration and Attack Damage runes, (although both will have very little benefits after 10 minutes into a match up).


In the first build, this seal is recommended since you don't need that much armor besides early and late game (which we build a Sunfire Aegis anyways). Early game, most AD champions have a total of 30 armor penetration (from Mastery Trees and runes), where armor per level runes will not help. Flat Armor improves early game weaknesses without sacrificing too much. Flat Mana regen or Mana regen per level seals are also very usefull.


Many downsides to magic resist is that it does not naturally increase over 60. To compensate for this, we use magic resist per level runes, which bring magic resist to a nice amount without even buying any items. Flat Magic Resist runes or cooldown reduction runes are also a nice alternative.


Although I use these for early game dominance and survival, armor penetration can also be substituted here. Yorick is extremely squishy at his lower levels so I suggest you keep these runes unless you are running a doran's item, or going 0/21/9 on the mastery tree.

Yorick is an extremely versatile champion. I find 0/9/21 better for myself as I prefer lane dominance using harass, therefore I need the extra mana and cooldown from it, otherwise he can run any mastery set. The only points he doesn't benefit from is the summoner spells he isn't using and Archmage's Savvy

This is the basic set for any Attack damage melee champion. You should get used to this set now, because it will stick with many other champions such as Xin Zhao and Tryndamere.
Exhaust slows the enemy target, when coupled with Omen of Pestilence will cause them to almost stop moving completely.

Ghost is used to escaped ganks and many un-needed battles or conflicts you cannot win.
Flash is ghost, just used differently for an extra surprise. It should be taken if you are jungling, but if you still prefer ghost, keep it.


This skills are okay for Yorick, but I suggest the three above.
Ignite is only useful against enemies such as Swain, Warwick, and Dr. Mundo. Unless you're against one of them, you probably don't need it.
Teleport is useful for making round trips through the map quickly. It's useful if you want to stay in the lane longer. If you aren't going to take blue golem a lot since your jungler needs it, I suggest you try this spell.
Cleanse is self explanatory - it'll help Yorick since he can't cast his ultimate when he's dead.

Any other spell is off-limits!

People don't realize how IMPORTANT this item is to an offensive Yorick. He will completely gain the 1000 bonus mana by 30 minutes - due to his 3 low cooldown spells, which should be used whenever possible after obtaining the tear of goddess. Many people will say the item is useless since Yorick only has a mediocre mana capacity. This is entirely false. With a full manamune, he has 2245 mana, allowing it to give more attack per gold than a B.F. sword does. To add, you will be building a banshee's veil and a trinity force to add more. This leaves 2845 mana - giving 77 damage from one item. The 2845 mana also increases your health regeneration by 28 per 5.


Hit harder with each spell cast.

the rest is under construction.