This Alistar is meant for an early lane destruction, and late game tanking.

I chose these runes because some are effective in the short-run and some are good for the end. If you are short on ip and have armor penetration runes work well too. It is also good to have extra health in the beginning. In the end it is helpful to have the cool down reduction.

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with this build there is a lot of mana so on the defense monasteries, I like full 3 on armor and magic resistance, then the important part of this build is the enormous amounts of mana, so being able to get 1% of it for health regeneration is huge, anywhere between 10 and 30 or more throughout the game because of tear of the goddess . then obviously you want to fill defense out to the max by taking all of the top tier masteries. Then even though the build is built to dominate early I like the utility to be dead less and get more gold and experience than the foes.

fist I start with sapphire crystal and two health potions, build to tear of the goddess. I always try to start with tear of the goddess first, then get sheen and boots of speed, then finish to mercury treads. The defensive items after this are for tanking, and are purely suggestions because all teams are different and require different styles of defense, so you have to adjust accordingly, but sheen and tear of the goddess are a must to level early. If the game becomes extended and you get tons of gold you can upgrade tear of the goddess and sheen to the next levels

I always start with headbutt because it can be a great defensive ability, or it can be used to scare foes by not letting up any ground. If you are laning with someone who has a stun it can be paired for early destruction. Then I usually go with pulverize to combo with headbutt, but if it seems to be a losing battle early triumphant roar can be a level 2 ability for defensive purposes. later with sheen, triumphant roar can be used to increase attack damage due to its low cost and short cool down if you are killing minions all while healing yourself, and keeping you in your lane longer for xp and gold. And my favorite part of alistar is his ult. Alistar's ult makes turret diving easy, and you can destroy turret huggers with ease and a little help from friends. Basically by taking turret aggro then reducing it from golf sized hail to basically just a small down poor that won't ruin your day, but you have to be quick you have only 6 seconds at first. Its easy to fool the foes, sometimes you can go gank mid, sometimes you can run and attack from behind, ulting, and then headbutting them out of turret range, then pulverizing to keep them in you teammates attack range. Also VERY IMPORTANT spam the heal. One for the obvious reason, it heals you and half to all friendly units (yes, even you, minion), two it activates sheen for even more damage and helps increase the chance of a last hit on a minion, three it build mana with tear of the goddess, and FOUR(wait, 4 thats like a really big number, right?) it activates collosal strength increasing further damage and can easily kill minions, and even kill champions. If you kill minions quick the cooldown goes down,so it can be used multiple times in short periods.

i like flash for two reasons. one flash allows you to catch up and cause an early destruction of fleeing foes of the all mighty aliSTAR. Two it is great for late game tanking. Which brings me to ghost the second spell, which is chosen for the same two reasons. both spells help to fill the the two different roles that alistar fills as an off-tank.

Alistar is a boss. even though that is all that needs to be said i will say if you are good with you ults timing you can make any enemy turret your friend.
Remember Alistar is not a killer and requires team work and turrets.
Alistars don't kill Champions, turrets do.