Hello, This is my alistar build that I use to play, I would love if you guys could give me some feedback. This build focus's solely on being the bot alistar and letting your partner farm while you zone the enemy out and heal when needed(Heavy CC included for fun ganks)

Pros:
-Naturally tanky
-Spammable heal
-Crazy CC

Cons:
-Has low mana so spamming Q and W will drain that
-Has a trouble dealing damage whatsoever
-No skins I consider awesome

The runes and explanations for such as as follows.
9 Flat Armor Marks - This initial boost of armor allows you to be the starting tank needed to successufly take hits for your lane partner (Especially skillshots) and even let yourself get focused a bit to allow your farm partner an early double kill(Happens more than you'd think)
9 Flat MR Glyphs - These are the same reason as above and make level 1 skills do a good portion less damage.
9 Flat Mp5 Seals - The Mp5 for Alistar is amazing, You can literately spam your E(Heal) constantly without worrying about mana which allows for a harder push as well as an anti harass.
3 Quints of Gp5 - At first I was questionable about if I should take these quints as opposed to more tanky ones however I crunched some numbers and here are my results.

Time you Start getting gold : 1:30
Initial Gp5 (With/without quints and masteries) :17.5/13.5
Time it takes to get enough for Philosophers stone (With/Without) 7:42/10:04 (2:22 Difference)

So as you can clearly see your trying to be a good support those 3 quints and the mastery allow you to get philosophers almost 2 and a half minutes earlier. This is a significant difference because it allows you to get your first GP5 Item faster and thus your Second and thus the rest of your build. It really snowballs and becomes very viable.

For the masteries we are focusing on utility with some initial defence.

The 6 points we have in the defence tree give us an additional 6 MR and 6 Armor to stack good with our runes for defending.

The other 24 points go into our utility tree to enhance our summoner spells, increase movespeed, Increase xp, Increase gp5, Increase mp5, and Decrease cooldowns.

This allows us to be tanky while still having great support masteries.

For Items your core is Merc Treads, Philo Stone and Heart of gold.

Mercury Treads - MR, Movespeed, and Tenacity
(If the other team is either doing poor AP damage, or has no CC Switch for Ionian boots, or Swiftness)

Philosophers stone - GP5 Mana Regen and HP Regen, what more could you really want.
Heart of gold - HP and GP5 Getting this item second can keep you tanky while not being to tanky that its going to waste.

For the rest of your items you just really Want to play it by ear and choose to counter.

Sunfire Cape - Get this first if they have high AD or a mixture as the health helps everything.
Force of Nature - Get this first if your finding they have good AP.
Warmogs - If their is an abundance of True or Poison damage (rarely is) Get this

You do not want to upgrade your GP5 Items until the very last because it removes their gp5 Abilities and you loose out on money.

I sometimes throw in an early kindlegem if I feel that I could use a little bit more Health.

Everytime you go back (but only after you get all of your Gp5 Items) you should be buying wards, wards, and more wards. If they are also warding, switch it up and buy the Vision ward every now and again.

I recommend you buy wards even if you dont know how to use them just having them and using them will teach you overtime.

For your skills You only want one point in your Q and W until you max your E. The reason being for this is your not trying to do damage, and you dont have the mana yet to sustain frequent stunning. More points in them means more Mana Cost and a lower cooldown that wont even be used.

Also quickly raising your E will allow your heals to become overpowering for anyone who is trying to harass.

For your first skill you should pick Headbutt. This skill provides the most CC and use of the 3 choices. Your Heal is useless at level 1, and your Pulverize is just a stun. The headbutt with proper placement can not only stun the enemy, but put them in a very compromising position that they don't want to be in. This generally causes early running which allows your lane partner to pick them off as they flee.

For summoner spells I have chosen Teleport and Clairvoyance.

Teleport - I believe this to be the most underused teleport spell, It is amazing especially in Summoners rift where distances can be great. It also allows you to head back to the shop and back to lane extremely quick. Another amazing part about this spell is it allows you to achieve awesome placement. You can teleport to mushrooms, turrets, minions and wards. This allows you or a teammate to place a ward in a bush, you teleport behind the enemy when they push past that bush and then headbutt and pulverize them when your team initiates. They wont know what hit them. Teleport, try it.

Clairvoyance - This is such an amazing spell, If one team has CV and the other doesn't it gives them a HUGE advantage. This spell has such a low cooldown with the masteries (40 seconds) so you can get it off 3 times before the minions even reach turrets if your quick enough! Use this to check bushes so you dont have to facecheck. Keep an eye on the top lane too and be cautious as to if enemys are mia or just hiding in the bushes. Use this spell to find the jungler, or check on dragon, baron or any of the other buffs. Everytime needs one person with this spell. It is a godsend.

You are an amazing farmer, but o so generous. A good support should have 0 Creep score, You don't want to steal any from your lane partner who we are trying to get fed, you should also be busy zoning out or scaring the enemy by popping out of the bushes and running to them and than running back (It works almost every time, they get scared and take off as soon as you leave the bush providing good zoning to overcautious players.)

However a great support should do all that and still maintain at least somewhat of one. As the support laner everytime the person you should be supporting leaves you need to get any kills they are going to miss. These precious last hits on a support can be immense especially on in order to get your GP5's.

So yes, You should farm, but only when no one else can.

There is a large number of Alistar players who I have noticed are not aware or unable to perform this combo, what combo you ask? The best combo ever made... ever.

This combo is A ranged stun that deals some damage, and puts you beside the enemy and in the middle of pain(in teamfights anyways) and pain is where you as a tankier player wants to be.

It is simple to perform but hard to master. What you need to do is Headbutt towards your enemy and hit Q or Pulverize mid Headbutt, what this does is pulverizes mid headbutt and sends the enemy in the air instantly from afar. A wonderful time that scares everyone.

Learning to master this can be incredibly aggrivating. Especially when you use smart cast such as I do. I recommend some bot games to practice or a solo custom game and try it on some minions. Practice always helps.

My method is to line up my Headbutt so I know its in range to cast and then hitting W and Q directly after as fast as I can, this almost always works.

What Smartcast does is makes it so that your spells go off at wherever your pointing (like karthus' q) This eliminates the slight delay between hitting the hotkey and clicking which can be significant sometimes especially with skillshots.

The only downside to this is you dont get to see the range of your skills, however playing a couple games like this and you will know the ranges as well as not be able to go back to the old slower way.

To Summarize this guide is for a Support and Tanky Alistar, by endgame you will generally have no kills, few deaths, and lots of assists. If you enjoy being the star or the carry than I dont recommend this guide or play style. You are the backbone of every team you are on and support them ultimately even if this means letting yourself die to save a team-mate or two (especially if they have a kill streak).

Goodluck playing alistar and I hope you enjoyed my guide, Please comment below this is my first guide.