Jungle yorick is terrible in my opinion, because none of his itemization issues are really helped by items you would normally pick up to jungle effectively.
He's not bad in lane though. Pretty much impossible to drive out of lane once his E gets going. Don't take manamune, learn to manage your mana instead of spamming like a noob. Philo stone + HoG early are the way to go, then grab boots3, Atma's, and see how the game is going. If you need to be tanky, grab warmogs for the giant health pool, force of nature or banshee's for your MR item if taking lots of AP damage, or thornmail if taking lots of AD. Then pick up a late game DPS item - frozen mallet or infinity edge or black cleaver, imho. Upgrade philo stone to elisa's miracle. Flash Ghost summoners. You are really hard to kill because of tankiness, your Q speed, your W slow, and your E lifesteal, and summoners. And you can chase because of all the same reasons.

Mas stacked up with other items I grabed such as bv that gave me mana, so Mas gave extra attack damage from those items. With just the latern and Mas I had nearly 200 attack damage, plus no shortage of mana. Further, spaming his skills is the only way to take advantage of his passive which makes him hit much harder with more ghosts out.

It worked with my play style of using him like a nuker with his skills. Which to me, he is basically like any sort of mage. I played him as such to great effect. Hide in the bush, pop out my three skills on the target. Auto attack and continue to spam, till:
1. the team gets a kill
2. they get away
3. It looks like a trap so I run like hell

Going straight dps with him would work for him with your play style, and again, how are you going to take advantage of his passive unless you keep the minions up?

Everyone knows Sivir is the weakest champ

Yorick is the worst champion. He is the bottom of tier 4.

Other than a slow (pfft) Yorick has nothing going for him. I don't CARE if you did really well with him, that's cool, great, go away. The fact of the matter is, he fills absolutely NO roles, has NO initiation, has NO lane presence, has NO team composition synergy, has NO defining attributes about him (other than his mechanics, which, by the way, sucks at the moment).

TL;DR wait until he's buffed.

He is essentially nunu with a hybrid zilian/ morde/ shaco ult. i dont know how many people have tried this but build him ad tanky, like you would build a nunu then ult bot your tryn/physical carry. You have a clone of them doing the same damage. Ever been hit by 2 tryns and the same time, it hurts. I do think he needs to be able to jungle because he would play like a smarter trundle. Give it some thought.

OP has only played 3 games as Yorick and all are custom games... self explanatory but how do you expect to have a "serious debate" about yorick when you havent even tried him really? Pathetic gtfo

Whenever you see someone say : Yorick does not suck, its just you guys who don´t know how to use him... You automatically know they are failing at logic, maths, gameplay skills, understanding of the game, and ultimately life.
I´ve won a few games using Yorick , that really doesnt prove anything than the love i´ve had for a champ who costs me a week´s worth of playing of IP.
Yorick sucks, deffending him and saying he is good makes you automatically a bad lol player.

Honestly, he's underpowered but fun to play. Hopefully he gets a buff so he's both fun to play and at least average. Any build/item suggestions I offer are for people who just enjoy him, and want to maximize what there is as much as possible.