This build is strange I admit, but I have been dominating Dominion with it. Its going for Tanky DPS with very high movement speed and with it Blitzcrank does a very surprising amount of damage even from the beginning while being able to jump from point to point capturing and defending both.

If you like more Cooldown Reduction on Blitzcrank, use the second build.

Movement quints to make his Overdrive faster. Attack damage, armor and magic resist for an extra boost at the start. Pretty simple and solid page.

You can change up the masteries if you like, I like more Defense maybe you like more offense or utility its up to you.

Utility works great with the build too, giving him more mana which means more shield and increasing his movement speed further is always nice.

He does a huge amount of damage without the Offense page so I think it could be used in other areas for a better outcome.

Manamune-
Blitz has a small mana problem this takes care of it, it also increases his mana shield greatly which comes in handy, spamming Overdrive and Power Fist makes it get up quick and gives extra damage. Now with the upgrade Muramana it is even more of a reason to get it.

Trinity Force-
Always get sheen first, works fantastic with Power Fist, really bursts someone down quick.
It gives extra movement speed which is very valuable for Dominion, extra damage, some slow, some health, Its a great item for Blitz.
I always grab Zeal after Sheen for the increased movement speed (I like capturing points early on) but you can get Phage if you like.

Mobility Boots-
Its Dominion where movement speed dominates! Makes capturing points unguarded a breeze and when you get hit and it brings it down to Movement Speed 2, just use Overdrive. Switch to Mercury's Treads if they have a CC heavy team.

Thornmail-
The most OP item on Dominion; let me explain.
Everybody grabs AD carrys, Master Yi, Nocturn, Tryndamere, Xin Zhao, Lee Sin, Gangplank, etc. They will be killing themselves while you do massive damage to them, with this item I have been able to solo Lee Sin, Master Yi, Nocturn and Gangplank and the likes.

Odyn's Veil-
This is if they have one very annoying AP ( Akali, Singed, Kennen) or two AP's. Good defense item and the extra damage is nice.

Sanguine Blade-
You will be able to get up the stacks very quickly with the attackspeed you have by now, with full overdrive and zeal. The damage is great and the lifesteal is greater. Keeps you alive and its easy to replenish health on creeps. When your passive shield activates it gives you a large timezone to heal your health back up in the fight.

While Overdrive is the most important move your speed will be covered by your quints and other movement items so you can lower the cooldown on his Power Fist.

Exhaust is a great spell especially vs all the AD carrys, it really helps before you have the Thornmail.

Revive who doesn't get revive on dominion?

Being fast and able to 1v1 most anyone you want is great for backdooring captures. you will want to be running and capturing points all the time, but remember he is great at Defending too, if you see a friend defending a point near you in need of help go to his aid!

You will almost always want the Shield buff in the middle everytime it appears, then they have to take down two shields to kill you. Plus it makes you look big and scary.

If you see multiple people capturing one of your points and your team isn't quite there yet you can kite them. Pull one of them and start killing him, the other team will want to go to his aid and will slow down the capture process, use your Overdrive and knockups to escape danger long enough for your team to get there.

Pros
-Best of all worlds!
-Almost unkillable with the full build.
-Great damage throughout the whole game from the first minute to the last.
-Able to 1v1 most and 2v1 some with full build.
-Great movement speed throughout the whole game.
-Great at Defending and Capturing and also stealth capturing.

Cons
-Not able to hold his ground without support early game.
-Hard CC can shut you down pretty quickly.
-Can't really think of any others.

-Be very very aggressive; even when defending.

-While defending keep pulling an enemy into tower range (try to aim for the squishiest one) and using your Powerfist to knock him up and keep him their longer, right when you hit E turn Overdrive on and beat on him. He should be dead or scared by the time he gets out of tower range.

-Never stop moving unless you're auto attacking someone, capturing a point or buying items.

-Try to be unpredictable, when people start getting used to my grabs I will just straight on bum rush them. Overdrive then Powerfist them beat on them rinse and repeat until he starts running, use your Rocket Grab then to finish them off. Not that they will get away, you should be faster than most every champion.

Do not knock this build until you try it, I promise you will be surprised and amazed how good this overlooked champion is for Dominion.