Garen - Tank - Solo top or top with shaco
Shaco - DPS - Top or jungle
Karthus - Ap mage - Mid
Teemo - Ap damage/Support - Bot
Master Yi - DPS/backdoor - Bot

If you use this on ranked will be hard to play shaco, so dont trust shaco on team, get like skarner to jungle, but ever have a prepared reserve champion.

U can just get rabaddon first then lich, but i suggest that because first.
Exhaust: U are squishy so u need take less damage.
Teleport: U are a fast pusher so u can do backdoors, and protect some places.(Or u can go support and use CV).
Runes: Like exhaust u are squishy so u need dont die so fast.

Questions.
Q:Why im going get runes of def,etc... With a killer or scouter.
A:Because u can kill eazy, using that u dont die eazy to heros like gankplank with his Q, and u dont take to much damage, making u survive more on teamfights.

Q:If i go ap, its most to scout no?
A: u can do backdoors with your ap damage, and teleport, and also, its eazy to prevent heros if u just mush all the lane, and heros like Miss fortune will not have any chance VS you.

So that is all.

U can get some items, dont need get wit's, if u can u can get like other rabaddon or also a mejai/guinsoo blade, i just suggest wit's, because is cheap and good.

Q:Why i will make so many damage?
A:Because your decieve alredy do critical, if u get the max damage of shaco + bloods u will get a High decieve damage and do some lifesteal, generally i dont get edge, instead i get a sword of occult.

Q:And phantom dancer, why i will get him last?
A: I only put that because some players like phantom, but i dont get generally, i get more damage, then phantom only help with Speed.

Q: Why a dorans on begin?
A: Because you need have mana to put boxes, use decieve all time and do some damage, its for mana regen, you can get a menki pendant and some pots over, but i preffer dorans ring.

You can also get exhaust or teleport.
Or for jungle ignite and smite.

Q: why so many warmogs?
A: Because your passive heals in percentage, then you will get very tank and stable on battles. And will stack with atma getting more damage to your abilities.

Q: Why so many archangels?
A: First, for the best ap in game and to let E activated all the time.

Q: Why clarity if i can get exhaust?
A: You can get over ignite, but clarity is for make a good begin.

Q: Why have 7 complete items?
A: you can get black cleaver/blood on final, or sell wriggle and get blood.

Q: Why have a wriggle?
A: Because yi is a backdoor guy, so for eazyiest backdoor, and good cs, he get wriggle, also a good start item with armor+lifesteal.