this is stil a work in progress, and i will polish it after how much interest there is in it.

other than that; thank you for reading, and i hope you will find it usefull

I know this set-up is a bit controversial, but it's a compliation of my experinces as a rammus mail player.
besides, as the headline says, it's for an aggressive, split pushing, dualist rammus build.
in my expeience, if you only stack HP and armor, or MR when nessesary, you'll be at the mercy of your teammates to secure kills, and you will be vaulnerable to roaming camps with high burst, no matter how much armor you have.
i usually play fairly defensive early game, and with this game i'm usually able to take on champs who have accumulated a lot more gold through kills and/or minion farm.

i go for health regeneration, armor, movement speed and cooldown reduction

i see many pick flash on rammus, and argue that you can flash over minions in ganks.

first off, there is a chance you will hit the minions, and you will have ended power ball before reaching the enemy, giving them time to escape, and you will have wasted your flash, and look like a donkey.

with ghost you simply go around behind the minions, and catch you enemy on the retreat, and if they choose to go towards allies, so much better.

the only thing in this scenario, is to choose to gank then minions iis NOT coming in, as the duration of power ball will probably not be long enough to go all around, and the minion will targetr you, it being likely you will hit them and end power ball. should you manage, it will have giving the enemy time to prepare for an exit, or bursting down you and the laner, possibly resulting in one or both your deaths.

but and by all means, if you're most comfortable with flash, i recommend you stick to that, but ghost present opportunities of catching low health enemies that flash simply do not.

especially with an enemy leave a fight with low health inside inner turrents, along side with homeguard boots, you have a real chancce of hunting down the enemy. or just coming your team to aid after split pushing, in no time.

it is worth noticing, that between runes and masteries and buying frozen heart, you will have around 37 cooldown reduction at lv 18, wich is great for catching enemies with Q, and use it to get out of a sticky situation, faster than you had planned. also W will be ready almost as soon as it ends, and R wil have under a minute cooldown, wich mean you can roll around the map, putting out insane amounts of damage over the course of the game.

this can be a bit risky build in a ranked situation, but if you can manage to avoid getting caught off guard, i think it should serve you well.
unfortunately i can not comment on it's effectiveness in higher ranked settings.

This is why i build tiamat after thornmail. spending less time farming jungle or pushing lanes mean there is more time to roam and be in the right place at the right time.