Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Amumu is one of the most overlooked champs in the game. He is a great tank, and I hope that this build can show that. Keep in mind that this IS my first build, so go lenient on me. I would appreciate any feedback you have that would make this build better.
My choice in runes are quite self-explanatory. Health per level seals and quints, and magic pen marks and glyphs
For items, start off with a Doran's Shield and a health pot. The shield will allow you to lane longer, as it adds much needed HP and armor.
After that, I usually go for the Ninja Tabi. The armor really helps, and the dodge can really come in handy in a tight spot.
After the Tabi, go for a Heart of Gold. Again, the armor really helps, and you want all the gold you can get. After you get the Heart of Gold, get the Warden's Mail. The passive is nice, plus the stats it gives are also really nice. Your next item should be the Randuin's Omen.
By this time, you should have around 150 armor, so that should add 0.5 seconds to the active ability of Randuin's. This item can be really good for getting away from a bunch of enemies because it slows them. And for every 100 armor/magic resist you have, it adds 0.5 seconds to the slow.
Go for a Negatron Cloak. It's time to bolster your magic resist now. After the Cloak, go ahead and complete your Force of Nature. This item gives the most magic resist in the game, which is much needed if you want to call yourself a true tank.
The next item you want to be working on it the Sunfire Cape. Start on your Sunfire Cape by getting a Giant's Belt. The only good thing here is the HP. This is where you go for your Sunfire Cape. This item, along with your Despair skill can really put the hurt on enemy champs, especially those that stack HP items.
Now it's time to work on your last item, the Guardian Angel. Start by getting the Null-Magic Mantle. When you get enough money, turn it into a GA, and you should be set to tank just about everything.
Just keep in mind that your build can change depending on the circumstances. If you're dying a lot, I would rush the GA. If the enemy team has a lot of physical DPS, then exchange the GA for a Thornmail. Other than that, there really shouldn't be much you can't handle.
If you want to be a big stronger against mages though, get a Wit's End. The magic resist might not be a good as other items, but that 42 extra damage and mana drain sure are. If a caster doesn't have mana, he/she can't use their skills, which makes for an easy kill.
Passive- Cursed Touch
This is Amumu's passive. His attacks lower the enemy's magic resist by 15/25/35 for 4 seconds
This is Amumu's skill shot stun. It has a pretty good range, and stuns on contact, and pulls Amumu to the target. This is a great skill to use for initiating/ganking as it IS a stun, and allows you to use your other skills.
This is Amumu's toggle spell. It's the HP item stacker's worst nightmare. it does a base 8 / 12 / 16 / 20 / 24 and drains 1.5 / 1.8 / 2.1 / 2.4 / 2.7 % of the enemy's HP. So the more HP you have, the stronger the attack.
Your main burst damage skill. It passively makes Amumu tougher by reducing the amount of damage he takes, and deals decent damage when activated. This will be be your main farming attack. Learn to use this wisely and you can completely annihilate entire creep waves.
Curse of the Sad Mummy
Amumu's ultimate. When activated, it stuns any enemy within it's range for two seconds. This is a great skill to stop fleeing champs when ganking. Position is key when using this spell. Try to get into the middle of your enemy's to use this to maximize the stun.
Now for this build, I use Ghost and Ignite. Since Amumu doesn't have any escaping skills, ghost is a must. The second spell is totally up to you. I prefer to use ignite, because it can kill when you can't. You could use flash or cleanse though.
You want to lane with someone who can harass, since you can't. You want to play pretty passively. Don't overextend yourself too much, and stun those who are foolish enough to do it on your side, preferably stunning in front of the turret.
This is when you should be starting to gank. Amumu makes a pretty good ganker because the reach on his stun. You should initiate with Bandage Toss, then activate Despair and spam Tantrum whenever possible. If you find yourself running out of mana, get blue buff.
This is where Amumu shines. There should be team fights breaking out all over the place, and you should be the one initiating them. Again, you should be opening up with Bandage Toss and spamming your other skills when available. Amumu is a very strong team fighter. Keep that in mind and you'll be doing good.