This build is only really for the items. I do not use these runes but I made this guide fairly quickly. The items are amazing, even OP with your ultimate. But I am not here to spend time on telling you guys how to play, I just wanted to share this discovery!

P.S Feel free to vote and comment, I will read every comment and hope to answer any questions.

Shaco's ultimate is amazing, and most build don't seem to utilize one key feature; It applies on hit effects. So I thought to myself, on-hit Teemo is popular, and incredibly effective for the simple reason that Teemo has high natural attack speed.

With this build Shaco has a natural attack speed of at least 2 per second. Now, with his ultimate, that is doubled, so 4 attacks per second. This is insane, and in my first game using this build I was slicing through Tanky-dps Lee Sin and a Jarvan IV with two Warmog's Armor and a Frozen Mallet.

if you are attacking 4 times a second (considering your ult is alive and attacking the same target) Then Madred's Bloodrazor alone is doing 16% of the enemies health per second. 6.25 seconds and a person would be dead, if it weren't for MR.

However, malady is already lowering their MR, and I'm not sure if you get get 2x max stacks because your ult counts as a second Malady, but hey-ho.

Even though it would be more like 10-15 seconds from just Madreds damage, you also have Wit's End, natural damage, abilities etc. You will do insane damage and be near unkillable via escape abilities and tankiness.

Since you are quite Tanky with this build, you can keep on slashing people for some time, in a 1v1 they will be dead because your slow + Frozen Mallet makes it very difficult to escape.

If by some chance you are losing a 1v1, you are Shaco, and therefore easily the best escape artist in the game. Hop over a wall, Ghost and mobility away, simple.

This build is only really for the items, I quite honestly spend too much time playing LoL to tell other people how they should play it, have faith in your own abilities.

Mobility Boots - Shaco's stealth is long enough for these to activate just after it finishes, giving you a massive speed advantage during a chase / escape so long as you don't get hit. Fairly simple reasoning here.

Malady - Great On-Hit effect item for it's cheap price and the attack speed, decent damage, useful AP and MR shred it gives. Great starter item, could be replaced with a Black Cleaver but the MR shred is good because Madred's Bloodrazor and Wit's End are magic damage, so you need the MR shred for full damage potential.

Wit's End - The Magic resist is great to help your tankiness, it gives nice damage, it is cheap and the attack speed is paramount to being a good on-hit effect spammer.

Madred's Bloodrazor - Amazing item. It will shred through tanks with the help of Malady, and will shred through anyone else at the same rate. It gives great attack speed and the armor helps keep you tanky. Because of your high attack speed, the extra AD comes in handy because otherwise MR can counter you somewhat. It may be expensive but it is your bread and butter.

Frozen Mallet - This item is tanky and the extra slow On-hit makes it damn near impossible for anyone to escape you. Even while trying to escape you can send your ultimate to attack a chaser, and maybe slow them and grant you an easy escape. The damage is also nice.

Guardian Angel - The magic resist and armor are nice, the item is relatively cheap especially compared to Madred's Bloodrazor and Frozen Mallet. Ofcourse the main benefit is that in the time you spend between death and revival, you may have gained the cooldown of Decieve back. This means you can often get an easy escape even 1v5.

Feel free to add in health, mana, oracle potions etc. when you see fit, remember this build is not set in stone, if the team has 3 ad carries get Thornmail, if they have a super fed mage, get more magic resist, it's up to you.

Two-Shiv Poison Is my main focus because it is basically an on hit effect. The slow is insane and makes you incredibly good at ganking.
I take a point in it first because I find it is more useful than Deceive for the cc, and if Deceive is taken first, I find, the temptation is to use it for damage and not escape purposes.
Jack In The Box I max this second because after the first point in Deceive it is already capable of being used to escape. Therefore leveling it up is less beneficial to spamming JiTBs and luring people into bushes.

I prefer to spam Two-Shiv Poison as much as possible for the insane damage they will do once maxed. The slow is also perfect for ganks and harassing this can be swapped for Jack In The Box, and I often do, but I think the potential is higher with Two-Shiv first.

I think everything else is self explanatory, but again you have a bit of leeway as the guide is still mainly focusing on the item build. I often max Jack In The Box first if I want some fun.

Have fun!
Shaco is an amazingly entertaining character to play, this build gives you the tankiness to get in there and do your insane damage, epic escape ability and the great chasing you can do with this build makes Shaco even more fun to play, whilst still being great to a team.

Pictures coming soon, comment for any other sections you would like to see.