Alistar is one of those champions most people don't recognize. Alistar in the right hands can be an amazing tank, support, and back doorer - all in one. Thing is, he's hard to play, you have to time your spells right, keep waves of minions up with your heal, keep the enemy from dieing teammates, starting a team fight right, etc. And in this build, I'll show you how I play Alistar and how to do it.

Now you could substitute Clarity with Exhaust or Teleport, but I enjoy being able to stay out in the feild longer due to Clarity.

Now if you got a jungler on your team, Alistar can solo lanes easy, just don't greedy. Last hit minions, don't mess with the other heroes much, just play passive, and once the enemy pushes the wave close enough to your tower, flash near the squishiest, Pulverize, and heat-butt into the tower. That's almost a for sure kill, and if not, finish him off.

I always start off with a Ruby Crystal, then with clarity, I'm able to lane for a good amount of time, normally not going back until I've got 1.1k+. So once you b or die, you're going to want to buy a Kindlegem and Ionian Boots of Lucidity. After you get a good sum of gold, go and buy a Sheen, followed by Zeal and Phage, and finally getting the Trinity Force. Now, I personally like the Ghostblade next, it gives good attack and attack/movement speed, which is great for Alistar. Now depending on the enemy, I'd go Spirit Visage or Shurelya's Reverie, the Visage helps his heal, but the Reverie has the active. Now it should be late game, and Alistar needs to be more tanky, let alone his Ult is really all the tank he needs, Warmongs just makes him insane. And if for some-reason the game has lasted this long or you've been fed, I recommend getting Trinity Edge, it makes Alistar a Building nightmare, and a hero nightmare in the right hands.

1-6 should be mainly you attempting to last hit, and trying to bump the enemy into the tower. I always try to lane with someone with a stun, so I can bump, have them stun, then once I'm their, stun aswell, normally ending up with the first kill. Once your 6, and have a sheen, you can attempt to tower dive. Mid game you won't have much trouble, Alistar is tanky enough normally that you don't need any tank items at this point, so it's you back-dooring or team fighting mostly. End game isn't much different, but at this point you'll need the Warmongs or somesort of high tier tank item to keep you on par, but you'll be aiming to take down turrets quick and getting out just as fast. In team fights you want to pick the squishiest enemy, and bump them to your crowd, this can quickly make the fight a 4v5 and knocking out their carry. When attacking anything, you need to make sure your using your Sheen/Trinity Force right, if you have to pulverize a tower just to get a big hit, do it. If a enemy attacks you while your killing a turret, Ult up and bump them away, and finish off the turret.

Pros

You'll be a great credit to team
Can lean any team fight to your advantage
Can tank anything with the ult up
Can kill a enemy single handed, unlike most Alistar builds
Can destroy any building with Ease

Cons

Will mostly have Assists
Hard to get used to
Not the best tank with out ult up

I use this build or something close to it with every Alistar game. The only Core Items to this is Trinity Force, Boots, and Ghostblade, everything else is subject to change. The build is hard to master and is fun to play. Farming isn't hard with this build, don't be afraid to ult agisnt big creep waves, and the blue buff helps alot. All-in-all, this being my first guide, I hope I help at least 1 person out, and I look forward to seeing more Alistars out in the Feild.