Just so you guys know this is my first build. I need as much input as I can get, because I would like to make this as great as I can.

My shaco build is very similar to many shaco build's the difference is my choice to include madred's bloodrazer as well as phantom dancer

i find that many times shaco tends to fall off during late game and become useless except for his aoe fear and his slow

i find that with the recent "nerf" to shaco, hes has been substancially buffed

with his late game damage increasing instead of falling off as it did before, he appears to have been buffed overall

this is why i no longer accept his inevitability of failure late game and decided to get in the fray

as far as runes go, I combine several sugggestions

i get a few attack speed gylphs and marks as well as all attack damage quints

i also am aware of the necessity of defense since shaco is indeed a very squishy champ, so i get all armor seals, since the most common form of damage is direct AD, but always aware of pesky mages, i get a few MR glyphs

now for my armor penetration, its true, shaco deals nonexistant damage without armor penetration... hes not a carry, grab some armor penetration marks and we're good to go

honestly? i grabbed these masteries from Dante Rebellion's build, but i replaced his reduced death time mastery point with enhanced recall mastery, i find id rather not die from recalling faster than dying and spawning faster, true in bad game the reduced dead time can help a lot, but in a good game (which is probably more often, and is usually what we focus on) reduced death time doesn't help work a donkey's ****

Madred's Bloodrazer is probably one of my favorite items. It gives you the ability to wear down the tank while your carry takes down all of the other champs on the other team, and allows you to f**k with all of the other players when they expect low damage output from shaco. Their ignorance is your bliss. I also added in phantom dancer for that end game damage which can make a difference. See the team work section for my reasoning for not including Guardian Angel

when you purchase Bloodthirster, I'm aware that there is no space for the item. Replace wriggles. I find it is helpful to wait until you have the 3k saved up to replace Wriggle's Lantern before adding another item. The bonus gold from Avarice Blade is worth not getting Youmouu's Ghostblade quite yet.

This is really the only good skill sequence for Shaco. His main damage output and disable is from his Two-Shiv Poison. His boxes are great but don't need to be maxed out right away due to the nerf to their duration. Also his mini flash/stealth is a main ability but it's easily used effectively at level 1.

These are very important. Ive seen Shaco's use flash. But its unnecessary, since he has a Flash inbuilt without a ridiculous cooldown, and besides that, it adds stealth. Flash is rarely useful. Ghost is viable for it escape but i find with phantom dancer, trin force, and mobility boots, i rarely need more movement speed to escape even warwick.

Smite and Ignite is awesome. Smite is necessary in jungle, and ignite is OP for teamfights especially against Tryndamere and Kayle.

Heal is viable... if youre a low level summoner or you feel you don't have the time to recall ever.

Pros

Very Fast Jungler
Able to gank in under 3 minutes
Able to have up to 5 kills in less than 6 minutes as well as plenty of gold and minion kills
OP Escape Tactics
Evil clown.

Cons

Squishy
Hard to play if not fed
Clone sometimes bugs out and doesn't listen

Shaco is difficult to play if you don't understand him. His clone is OP when used for avoiding abilities or distracting the enemies. Also it can be used to kill dragon as early as level 6 (you need blue buff, smite, and full health(ish))

SHACO IS ALL ABOUT POSITIONING.

you will never die if you are able to place a box in the middle of a fight and q out of the fight, if anyone chases, slow them with your two-shiv poison

ALSO*
make sure you attack from behind whenever possible
shaco's damage scales up considerably if you are able to attack from behind

At 44 seconds, place a box at wraiths, then place 3 boxes at red buff, run back to wraiths and kill big wrath and a small wrath, then run back and kill red buff *SAVE SMITE*, now run over to blue buff, place a box, wait until the box goes off and wait for the golem to become un-feared, and begin attacking from the back until the golem is dead. Use smite this time. I prefer not to use two-shiv poison too much until they are low health since the passive causes the minions to miss many of their attacks. Now it is time to gank Top, then Mid, Then Bot, before recalling, and moving back to the jungle to finish the wraiths and the wolves and golems. Clear jungles and gank as needed, if you are jungling shaco, you should be pretty familiar with jungling or you will have a hard time. Use common sense, don't jump into outmatched fights, but if you have a decent chance of turning a fight jump in.

ATTACK FROM BEHIND ATTACK FROM BEHIND ATTACK FROM BEHIND
i can't stress this more. With this build, positioning is easy, but save your q for escape, and stay by walls. But with this full build you can deal massive damage from behind before retreating to another position with your q, use your boxes to scatter them and make their carry easier to target

Lets be honest, Shaco is one of the most unique champions and is very useful in almost ever situation

Boxes, attack speed, and two shiv poison. That will be all.