this build is directed to 5v5 games. My main point is to make really fast tank who can catch everyone (only rammus can escape.. if he starts rolling fast enough).
Hope you enjoy it.

I choose this ones

Greater Mark of Insight x9 = the more magic penetration we gain = the more damage we deal
Greater Seal of Evasion x9 = why i didn't get armor or health? because we will gain armor&health through game, but dodge not at all. Imho it's saved few my lives
Greater Glyph of Shielding x9 = having more MR is always welcome
Greater Quintessence of Swiftness x3 = we need more movement speed. Rly.

The point was to give 3points in movement speed in utility tree and rest of point to defense.

additiona 2%dodge fits with our seals
+3% movement speed accumulate with +4,5% from quintessences. without any boots we start with 344ms
bonus health regeneration based on 1% of max mana perfecty combo with increasing by 5% max mana. in addition we will have a lot of mana, therefore it will increase our hp regen.
imo rest is clear

easy to understand - starts with fling, then maxing poison gas whenever its avaible.
ultimate on 6, 11, 16.
mega adhensive in same speed as fling.

or mega adhensive before fling. we do not need much dmg from fling

i choose ghost + ignite

ghost- when we engage enemy we need to get him as fast as its possible. also perfect for flee
ignite - guarante us easy kills in early game

in some guides plp tell why they didnt get other summoner spells. i wont, im too lazy

this items which i mentioned in 'item purchase' are totally needed. others are diffrent in many cases. You may get
Randuin's Omen for slowing everyone and give us armor. good item
Sunfire Cape - funny, but not necessery
Thornmail - perfect against enemy ad champions
Force of nature - gives us Mr, ms, hp regen
Abyssal scepter - reduce enemys mr also increasing our. if enemy team has a lot of mr and our casters have problems - we need it
wormogs - dont like it, but if some1 want, can get it as last item

You are the tank, u go first.
use Ulitmate+ ghost, then poison. grab the squishesd one and fling + mega adhensive - no chanche for enemy when our team arrive.
DONT WASTE GHOST AND ULTIMATE TOO FAST

when enemy flee mega adhensive is perfect to slow and then fling some1
Randuin's Omen - remember to use if you have to slow all around