Ordinatus

"A weapon the size of a Titan. A near-perfect expression of the Omnissiah's grandeur and, of course, his puissance. Armies are thrown to the wind by its glorious song, and mountains themselves skitter aside at its demand. Nothing stands before a sacred Machine Spirit so mighty without its consent." — Tech-Priest Garrulon Vyme, on an Ordinatus

When a Titan just can't get the job done, the Imperium of Man brings in the specialized war-machines known as the Ordinati.

Overview

Unlike the standard Titans, each Ordinatus is custom-built by the Adeptus Mechanicus for a specific objective and named after the world it was constructed on. A special branch of the Admech called the Centurio Ordinatus is responsible for their creation, use, and maintenance, similar to the Collegia Titanica. The Ordinati themselves vary widely in armaments, size, shape, and role- some are armed with guns that would make an Imperator Battle Titan jealous, others are designed to carry entire battalions of troops, but all are more than capable of winning a war on their own. Most of them are only used for one battle and then get mothballed.

It seems kind of wasteful given how stupidly powerful they're supposed to be, but you must first realize how Mechanicum see them. To AdMechs innovation is one of the most dangerous things in the world - if they invent a new Ordinatus it is only out of extremely dire need, and even then only Centurio Ordinatus magoses are entrusted to do so. After it fulfills it's purpose it should by all means be left alone, because it's a new technology, and as such using it without a very, very good reason is seen as sacrilege if not outright heresy.

However, actually deploying one is a very rare event compared to that of their Titan counterparts. Most of them were either destroyed, lost, damaged beyond repair, or just plain forgotten during the Horus Heresy. They're typically deployed separately from any Titan Legions or Skitarii, and are used only when any other options have failed.

Ordinati are protected by a specialized force field called a Dispersion Field, which is essentially a single oversized Void Shield. While it's extremely effective at repelling projectiles and energy bolts, its prolonged use requires massive amounts of power, and so runs the risk of overloading its own generator if used for too long. All of them but the Ordinati Minoris appear to have three pairs of tracks for mobility, although this shouldn't be considered a standard due to the way they're custom-made.

Ordinatus engines are absolutely massive land crawlers that can run over and squash Baneblades, and are protected by void shields on pair with that of a titans. Unlike the titans, Ordinatus engines are usually not meant to directly assault enemies, but tend to be better suited as really big back line artillery - they are (very relatively) squishy for their firepower and most times indiscriminate at unleashing said firepower, so they need support armies to keep enemies at distance.

Speaking about firepower... While titans and huge ass super heavy tanks tend to have multiple guns on them, Ordinatus engines always mount only one ridiculously OP weapon system. Most (if not all) of those systems were once specifically designed to solve one particularly difficult problem. Let me reiterate this: Mechanicum, the guys who see innovation as one of the most perilous things in the world actually invented things. Not just "in the distant past before much knowledge had being lost" but right the fuck NOW - some of the famous Ordinatus weapons were invented in M41 to fight off Waaagh! Ghazghkull. It's no surprise to anyone that the cogboys consider them the most sacred relics of all.

Ordinati Minoris

The "small" Ordinati, which are still each the size of three Leman Russ tanks lined up end-to end and are typically armed with weaponry normally seen on Titans. They're easily recognized by the four sets of tracks they possess- two at the front and two at the rear.

Ordinatus Mars

During the Schism of Mars, one traitor Magos holed himself up in a mountain citadel, sending his armies to harass Loyalist factories. Four companies of Imperial Fists led by Sigismund were sent to stop him, but discovered that the Magos possessed a peculiar xeno artifact that caused any ship that got too close to it to be blown up or thrown into the Warp. A ground attack was decided to be a more viable approach...if it weren't for the half-mile thick walls made of the toughest materials known to the Imperium.

The Mechanicum responded by creating the Ordinatus Mars, armed with a Sonic Disruptor that caused the citadel to shake itself apart with the force of its sound waves, allowing the Loyalist Tech-Guard to storm the citadel and execute the traitor Magos with no difficulty.

Ordinatus Golgotha

After Ghazghkull Mag Uruk Thraka fled Armageddon, Yarrick managed to track him down to the planet Golgotha. Some time after his capture by the greenskins and later escape, he returned with a punitive force of Titans and Skitarii. The sheer size of the Ork WAAAGH! made it impossible for them to gain an advantage, warranting the creation of an Ordinatus made specifically to deal with overwhelmingly massive hordes.

The Golgotha's Hellfire Missiles were perfect for the job, and routed the Orks within a week. Since then it's been deployed in any battle where the enemies of the Imperium outnumber even the Imperial Guard.

Ordinatus Armageddon

The Ordinatus Armageddon was designed during the First War for Armageddon to defend against a particularly dangerous horde of Daemon Engines. The plasma-based Nova Cannon it's equipped with is normally used on starships, giving it the ability to melt Titans in one shot and disintegrate entire tank battalions with a salvo. Supposedly, it was inspired by an old Squat anti-Titan vehicle.

Ordinatus Priam

Essentially the Hades Breaching Drill's big brother, the Priam was designed during the Siege of Priam to bypass the defenses of an occupied city by drilling directly through a planet's crust, travel through the mantle underneath, and then reemerge behind enemy lines. It was successful at deploying four companies of Imperial Guard to break the aforementioned siege, but was rendered inoperable afterwards due to its shielding partially failing during the attack.

Gallery

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  The Ordinatus Armageddon, for when you really need a continent bathed in plasma.
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  The Ordinatus Golgotha. How do they reload those missles, anyway?
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  The Ordinatus Mars. Suck on it, Noise Marines.