Eye of the Storm

Cooldown Cooldown Cooldown. Need I say more? You basically get to use WHIRLWIND so often that you feel bad for them. No one usually ever just straight up walks through one, it wipes minions completely out if placed correctly, and it can land you some kills without you having to even look at them. And in certain *cough cough* (gank) situations it's only polite to drop a WHIRLWIND at your feet (while turning 180*), enter SLIPSTREAM, drop a SPIRIT OF THE NINE WINDS in the direction you're running, hitting any arrogant fools stupid enough to follow you, and then ZEPHYR whatever's left. If you're smart, you basically can't die and can't get pushed too far back. It's mana-hungry though, so you need VAMPIRIC SHROUD and SALVATION, as well as MANA POTIONS. Then, it's "weather" or not you want WARDS or MULTI POTIONS, which depend solely on your preference of play. Aggressive = WARDS. Cautious = MULTI POTIONS.

Pros:
- Extremely Efficient All Game
- Great Pusher
- Hard to get Pushed
- Descent Escape
- High Power
- High Mobility
- High Sustain in a Lane (With VAMPIRIC SHROUD and PYTHAGOREM'S PIECE)

Kans:
- Mana Hungry
- Might have to take up your first Relic with Salvation
- Super Squishy
- Escaping Requires Skill (and Lack of Skill from the other Team)

POWER OF THE WIND JEWEL:
Gain Power equal to 5% of your Maximum Mana.
As tempting as it may be to build BOOK OF THOTH straight out of the gate, I've learned over extensive rape sessions with KUKULKAN that the Power is going to be there regardless so just be patient. It's a completely unfair advantage, basically giving him a ROD OF TAHUTI as a 7th item. But try your hardest to ignore this PASSIVE while you build what you need to be able to play your way to success.

ZEPHYR:
KUKULKAN fires a bolt from his mouth, stopping at the first enemy it hits, dealing significant damage to it and all enemies nearby and slowing them for 3s.
This move can help clear a wave of minions, help avoid a gank by slowing them down, or can keep an enemy in your WHIRLWIND for longer than they want. Oh, and stacks with GEM OF ISOLATION... because that's fair. Unfortunately, with KUKULKAN being as mana-hungry as he is, I usually try and weigh my options on using this ability. Will it save me? Will it secure a potential kill? Will clearing this wave of minions a few seconds earlier be a significant influence to the tide of battle? That is not to say that at a large percentage of mana I won't spam this for Maximum Damage Output. Definitely the second most utilized ability he has.

SLIPSTREAM:
KUKULKAN gains a speed boost for 4s.
While this sounds about as helpful as an ODIN ULT in the enemy's tower, the speed boost is a key weapon in my aggressive tactics. Use it from the fountain to get to lane faster, use it to get a quicker engage than they were anticipating, and use to escape a bad situation... while juking of course.

WHIRLWIND:
KUKULKAN summons a tornado at a ground target location, dealing damage to any enemies within it's radius, dealing more damage the closer to the center they are. Any enemy caught within the radius gets a smaller tornado branching off from the larger one, dealing damage every .5s for 2.5s, refreshing if they enter the tornado again.
This is the bread and butter. This isn't the cherry on top, this is the bowl of ice cream. The really really big bowl of ice cream. You want to be dropping these as frequently as possible: every minion wave, every team fight, every jungle camp, every enemy advancement. You want them to feel like they can't come anywhere near you. If you're in the SOLO LANE and you're facing a melee fighter, make them hate you for placing tornados on top of your minions. Dare them to come kill them. Starve them for gold as they're forced to wait for tornado after tornado to end while the tower takes your minions out. Make them dread advancing on you because you place these right between you and them. Make them feel stupid for hoping they can bait it out, and then remind them that you can basically place one right after the first one ends.

SPIRIT OF THE NINE WINDS:
KUKULKAN calls forth a dragon that breaths wind down in a line in front of him (similar to an air strike) damaging enemies and knocking them to the side.
This ULT does a ton of damage. Loads and loads. But its downfall lies in it's similarity to a train. If you're on the track you can see it coming and just step to the side. The trick to catching an enemy is getting them caught up in other things. Finding the enemy team fighting the Fire Giant is a good example. Catching them against a wall with WHIRLWIND is a good way. Slowing them with ZEPHYR before-hand always helps. But the best chance you have of catching them is when they're chasing after you while you're retreating. Especially melee gods that have to get up close.
That being said, with Max Cooldown on, your ULTIMATE is ready more frequently than you have opportunities to hit with it (in my experience anyways), so allow me to introduce you to the alternate option. Let's imagine the situation where you've been WHIRLWINDing your opponent so far back that they're just fed up with it and want you dead regardless of the pain they'll suffer to get you killed. They've timed it out to know when you'll drop your tornado and have guessed that if they get past it when it drops, you'll be almost defenseless. Your minions will be too preoccupied cleaning his minions up to bother with him and your WHIRLWIND will be gone for at least 6-8 seconds... he thinks. If you see an enemy running ahead of his minions directly at you, just use your ULT to clear the wave of minions. Your ULT actually costs less than your fully-upgraded WHIRLWIND, so it helps you mana-wise. It wasn't going to hit him in this scenario anyways (assuming he has half a brain), and your ULT will absolutely obliterate all his minions. His first reaction will be to dodge your ULT. He'll then feel like a boss because he thinks he just made you waste your ULT. But then he realizes that he's down the lane a ways, has no minions and has to face you, your entire wave of minions, and you still have your main abilities to fling at him. Early-game, you get the kill hands down if you play your abilities right. WHIRLWIND on top of him so that he can't really retreat, ZEPHYR him in the face, and SLIPSTREAM away. The minions might not clean up but he'll retreat and recall at the very least.

The first thing you want to get is VAMPIRIC SHROUD, feeding your mana-hunger. It might be the most important item in the entire build. I'm not recommending spamming yourself to no mana... well, not exactly, but you should definitely clear every wave that comes your way.

SHOES OF FOCUS, CRONOS' PENDANT, and PYTHAGOREM'S PIECE are essentially your main enablers. When you get Max Cooldown you'll be able to play in a way that makes you nearly unkillable and extremely dangerous at the same time.

SPEAR OF DESOLATION is too overpowered to pass up, especially if you get some truly stupid Cooldowns after a kill.

And BOOK OF THOTH is an essential as well, netting you a total of 170 Magical Power and 875 Mana at full stacks (If you literally bought 0 other items that is).

After BOOK OF THOTH, it's really a matter of taste. SOUL REAVER hurts like hell, especially against tanks. ROD OF TAHUTI just makes your overall Magical Power Rediculous, possibly even past the Max Magical Power limit. And GEM OF ISOLATION makes sure that enemies have to sit inside every WHIRLWIND that much longer, gives you a more massive speed bonus, makes escapes easier, and still gives you plenty of Magical Power to cause mayhem with.