Starting options:

Recommended aggresive ganks/standard start

+ x3


OR

Jungle sustain and easy clear

+

OR

Safe start items for no surpsises

+ x5

Early musts:

philosopher's stone + + (if you didn't already grab these)

These are musts because Rammus falls behind in farm quite easily so GP10 items will let you keep up with gold flow. The boots you get because everyone else has them at this point so ganking without them is just silly.

Early/mid game:

OR +

Late game:

+ +

After this, you can be flexible. Versus double AP which is a little rarer these days, consider Force of Nature. Versus high damage, Warmog's Armor can sometimes give you the tanking ability you need. Versus high AD, consider Frozen Heart or if you're facing double AD carries, consider Thornmail (otherwise try to avoid it).
The reason Guardian Angel isn't anywhere in this section is because there's no one time to get it. You should get it when you deem necessary because while getting it late offers the obvious advantage, getting it early (around level 6-9) can sometimes give one of your lanes a free kill due to the recklessness you now have the option of committing when ganking.

Otherwise, Rammus builds are pretty easy, just counter the main damage threat of the other team and you're doing your job well.

You see this?

That is an armordillo that runs around in the jungle then proceeds to roll his big a** shell into bi*ches and make fun of them in such a way that they slowly kill themselves by attacking them. Ya, he can do that.

If you wanna do this yourself like a baws, just keep reading, simple as that.

*NOTE

AD = attack damage
AP = ability power
CC = crowd control
OP = over powered
MR = magic resist

Pros

-Will mess any scary AD carries like Tryndamere in the face.
-Extremely quick jungle clearing.
-Good map mobility due to Powerball.
-One of the most devastating gankers in the game (that title would arguably go to Maokai or Hecarim).
-Easy to learn, low skill cap champion with simple rolls ( < see what I did there).
-Good presence after level 3 and in teamfights in the mid and later stages.

Cons

-Difficult to grasp his limits.
-Very often banned at lower ELO.
-Not such a good option against AP champions in the early and mid stages of the game.
-Easy to counter-jungle with champions like Shyvana.
-Falls behind in farm as the game progresses.
-Weaker than most tanks without Defensive Ball Curl on, especially mid game.
-Weak ganking presence before level 3.

Early Game:

When you jungle as Rammus, your first objective is to take the ancient golem otherwise known as the Blue Buff and to quickly clear all the way to your elder lizard or Red Buff in order to obtain level 3. Once at level 3, you want to be a constant thought in the enemies mind. You want to have them thinking, "I can push, but I really shouldn't because Rammus can gank at any second". Once this fear in instilled, try to look for ganks all across the map, because you can cross the entire map relatively quickly with Powerball

Mid Game:

Rammus is by no means a weak champion but this is his weakest stage of the game. Generally at this point, if you're doing well, your build will consist of your 2 GP10 items and your Guardian Angel and maybe elements of Warmog's Armor. At this point, avoid fights that may be risky and stick to your strengths which are your great initiation and ganking potential. Don't worry too much about bad CS because Rammus does fall behind in that category.

Late Game:

At this point you will have great defensive stats and you should be next to impossible to kill. An interesting plus to Rammus' high late game armor is that most times, Rammus players can have upwards of 250 damage, simply from their spiked shield passive, so this is where you can shine brightest.
But, this is also where you need to be smart. You are your teams initiator in almost any team composition so there may be times where you need to go balls deep into the enemy team. Fear not though, because late game your defesive ball curl is OP and your defensive stats will soar through the roof. Once teamfights breakout, your first target should be the AD carry. Generally, you want to taunt them in order to nullify their damage as most of the time they deal the most damage over the course of a fight and give your team the damage advantage it needs in order to win the fight. Once that's done, you win the game. :)
Keep in mind that Powerball can also be a great late game zoning tool as nobody on the other team would want to get locked up by you.

Must have:

Smite: You cannot be a good jungler without Smite, plain and simple.
Only exception coulld be Nunu & Willump due to his Consume.

Recommended:

Flash: This will allow you to blink over enemy minions that try to get in your way of making a good gank by blocking Powerball (NOTE: when flash is used while in Powerball, you will stay in Powerball form) and it's also a good escape mechanism to add to your Powerball.
You can also Flash next to people when they are near your tower and taunt them to get them to take tower damage pointlessly. Don't do this however if the enemies are full health, the long cooldown on Flash isn't worth the damage.

Viables:

Ghost: Yeahhh it's good and it makes your Powerball turn you into Usain Bolt x2 but unless your chasing one person in the jungle, Flash is just overall a better idea.

Heal: Good support spell and it will keep you alive longer aswell as enable Heal baits, but Flash offers overall better utility.

Teleport: This is kinda cool because you can Teleport to a sight ward or a Vision Ward in a bush and surprise the **** out of a lane.


Other summoner spells are not necessarily un-viable on Rammus they just don't offer the same benefits that these do.

Marks of alacrity

x9
- These are subject to much question but think about it this way, no other marks are beneficial to Rammus in any way and the bonus attack speed allows for faster jungle clearing.

Seals of resilience

x9
- These runes will boost your armor alot, and in turn increase your level 1 damage to about 65, making you one of the fastest jungle clearers at level 1 (you can't really beat Shaco).

Glyphs of shielding

x9
- These runes give you much needed late game MR.

Quintessences of Resilience

x3
- Allows you to tank the jungle like a badass and gives you the attractive option of starting with Boots and Health Potion x3

Another alternative that alot of people use and that works very well:

Quintessences of Swiftness

x3
- These allow you to clear the jungle quickly and be faster than most champions in the game with Powerball active. It does lower your tankiness and damage at level 1 however and starting with Boots is riskier with these quintessences.

These masteries focus on overall tankiness aswell as jungle survivability and increasing my movement speed, as all of these benefit Rammus exceptionally well.

I honestly tried and tried and tried to find alternatives to this but honestly there are none. All the other alternatives are simply not as good so here is my skill sequence.

FOCUS

> puncturing taunt > >

Skill explanations:

Soaring Slam:

Reasonably spammable ultimate. Good damage in teamfights and great damage versus towers.

puncturing taunt:

This is one of the best CCs in the game. It allows you to shut one person down for 3 seconds and lower their defensive stats significantly. Take a point at level 3 and max it immediately after Soaring Slam.

Defensive Ball Curl:

This is what makes Rammus tanky as hell late, and early game. The damage return also allows you to clear jungle creeps like no other tank can aswell as return damage to any champions foolish enough to attack you. Take a poitn at level 1 and max it by level 13.

Powerball:

This makes your ganks devastating and is also a great initiation tool throughout the game. Take a point at level 2 for jungle clear and map mobility, but max it only at level 18.

Spiked Shell passive:

Don't stack armor simply because of this passive. It's a nice bonus, but the 0.25 ratio is nothing to write home about. Basing your build around this is a common mistake.

The many uses of Powerball:

Powerball is Rammus' utility spell, and it is probably one of the most versatile utility spells in the game. There are so many great uses for Powerball like:

• Crossing the map in no time like a baws
• Escaping from scary situations
• Clearing the jungle very quickly
• One of the best ganking tools in the game
• Can be used to detect stealthed enemies like Akali or Shaco
• Great sieging and zoning tool
  
  An example of this spell's great utility is this. Say a teamate is being chased by the entire team and he's on a spree, a smart Rammus will Powerball himself into all of them to slow the entire group and save his teamate and with Shurelya's Battlesong, you can get away no problem.

There are not any super hard counters to Rammus but there are some champions that won't necessarily kill you but they could cripple you as a jungler:

Trundle:

- Agony ruins your defensive stats and his Pillar of Filth blocks good initiations.

Shyvana:

-Unfortunately for you she can easily counter jungle you and well she's a dragon (scary :o).

Janna:

- Rammus is an initiator and [[janna]'s kit make her a counter initiation and disruption champion so she can ruin your good engages if she's played properly.

These are just a few soft counters, there may be many more, but I just don't like these ones the most.

You should try to play Rammus as a jungler, although when I first played him, I saw the potential for a solo top champion, but his ganks are devastating.




Your jungle route should generally be this:
1: Use Defensive Ball Curl then use Smite to kill the ancient golem also known as the Blue Buff (1 on the map).
2: Grab a point in Powerball and use it to roll into the wolf camp then use Defensive Ball Curl and kill them (2 on the map).
3: Use Powerball to go to the wraith camp and use Defensive Ball Curl to kill them very quickly (3 on the map).
4: Use Powerball to roll into the elder lizard also known as the Red Buff camp and turn on Defensive Ball Curl then kill it with Smite (4 on the map).
5: GANK ANY LANE USING THIS NEW NOT SO SECRET GANKING FORMULA.

*NOTE
The green circles on the map represent spots you should defend early in the game aswell as spots that should be warded throughout the game.


Here is how to gank:

When the lane's bush IS FOR SURE NOT warded:

This is Rammus' NOT SO SECRET GANKING FORMULA. When you gank, you should first hide in a bush near the lane you are ganking that you are sure is not warded. Press Q to use Powerball then charge it for a second. Roll in on to your enemy to slow him with Powerball. Once he is slowed, use your E, puncturing taunt, to allow your lane to catch up to the enemy and then proceed to kill him. If you are level 6, turn on Soaring Slam as soon as you taunt your enemy (because if your gank fails and you use your ultimate, you will look like a huge derper).

When you think the lane's bush MAY BE OR IS warded:

Before you enter the warded bush you have one of three options:

1: Don't even bother ganking (lame).

2: Try to go around the other side or tower dive them use my NOT SO SECRET GANKING FORMULA.

3: What you should do most of the time is wait out of the ward's vision then inform your laner that you are ganking. If laner is someone like Irelia who has a good CC (i.e this doesn't always work with people like Mordekaiser), then tell him/her to initiate and use her Equilibrium Strike (her E spell in this case). As she/he is doing so, use Powerball and roll to the target immediately. Given as the target is CC'ed by Equilibrium Strike which is a stun/slow, the target will be like, "Darn, I'm getting attacked, and since I'm not Dyrus, I'm gonna not watch the river as I escape!" and will probably be more focused on getting away therefore neutralising his pesky sight ward. Then when he realizes he is dead, it's too late, so go ahead and use my NOT SO SECRET GANKING FORMULA and KILL HIM/HER.

*NOTE

If your laner is loser their lane hard, you should probably not attempt this as initiation may kill your teamate and make you look like a buttcrack.

Rammus is often banned in the lower ELO brackets but generally he's a good pick for a team needing a tanky jungler or some hard CC. Make sure that as a jungler, you always communicate with your team. A big mistake however, is only ganking the whole laning phse. As a jungler you must farm and if you don't farm you will fall behind greatly. Tell this to your team and try and help the laners in need as much as possible. Keep in mind that if your top laner needs help but your bot lane is pushig hard, stay in the top part of the jungle longer than the bottom part. These are simple jungle mechanics that one must master to be a good jungler in general aswell as a good jungle Rammus.

Map control is also extremely important, so try placing smart wards all around the map. A good jungler will try to counter-jungle a Rammus 24/7.
Here is a map depicting good ward placement spots:


YELLOW STAR= Defensive wards to protect your buffs.
ORANGE STAR= Counter-jungling wards to steal enemy buffs.
BLUE STAR= Defensive wards to prevent ganks.
RED STAR= MUST WARD SPOTS where the enemy can take The Dragon near the bottom lane or Baron near the top lane.

The importance of Oracle's Elixir in ranked

After your upgraded boots or Guardian Angel, you should try to buy the Oracle's Elixir. On most ranked teams, the jungler is the one who grabs this because he is the one doing all the roaming so he sees more of the map from levels 1-11 than any other role in the game. Clearing the enemy sight ward and Vision Ward placement will limit their vision of the map and therefore grant you more map control with smart ward placement. Oracle's Elixir isn't always necessary at lowere ELO brackets as some teams aren't even smart enough to buy wards of any kind and in that case, you should win by a landslide and also save 400 gold in game.

Well, you've gotten this far so by now, you know about 90% about what I know about Rammus.

I'll leave the last 10% of the arcane knowledge for you to find in order to keep playing Rammus fun and also to make sure you are a certified badass armadillo.

Also, if you've read my build, please comment about any errors/bugs/things that bother you so that I may fix them.

Thanks for reading! and good luck young dillowan.