flash lets you combined and land your skills so much better an example of this is Powerball Flash is great to flash over minions or terrain and slam into your enemies.

Smite makes jungleing faster can steal there buffs and a lot more is a must on Rammus or any jungle due to this factor just the best spell for him.

Your ganking tool your get there skill that skill that makes enemies instantly flash away use whenever possible to catch up for a gank to tower dive to escape this skill makes you one fast armadillo.

Its like if Thornmail was a skill this would be it but on top of that gives magic resist as well as armour great skill.

puncturing taunt

Use this to taunt the carries and disable them as much as possible to make your team burst them down.

Area of effect damages structures some nice damage per second can be used to damage a tower hard.

The rune setup I use gives me a lot of survivability when I do gank which and helps my defence for what Is what I lack for in masteries so I get good jungle speed and ganking potential

Other rune setups

Doesn't help jungle speed or tanking the movement speed is nice for ganking but is not required and makes you squishier when in the fight and less sustainable in the jungle.

I use these instead of the standard 0/21/9 because it is all defence which does not help my jungle time which is something Rammus needs to be improved and my masteries make ganking easier due to the increased move speed which is also useful for getting to camps quicker making your over all time in the jungle faster and getting to ganks even faster increased buff duration is a must he needs that first two blue after that the mana from philospher's stone will be sufficient I feel that these are the best masteries for my way of playing him.

I have selected these items because the double gold per five help me get some gold while I am ganking and pay for themselves late game and the heart of gold and cloth armor build into my randuimns making it a cost efficient build Banshee's Veil to stop heavy control spells stopping you from doing your duty.Of focusing there carry and disabling them through the fight and ulting and dealing lots of area of effect along with randuimuns and revrie if you need more magic resist get banshee's veil earlier.

lots of auto attackers only reason to get this

Rinse repeat you need them early ganks to help your lanes by blowing the enemies summoner spells and Rammus excels at doing this so keep pressuring them lanes