Taurox
The Taurox is a vehicle used by the Imperial Guard serving as a low cost APC. By comparison to the other Dedicated Transport available to the Imperial Guard - the Chimera - the Taurox is less armored (AV 11 on the front instead of 12), and can carry less than a Chimera (capacity 10 instead of 12). However, it has several advantages of its own. The Taurox is less likely to damage itself from moving through Dangerous Terrain and is shootier (arguably).
However, it also looks retarded, a bit like Orks looted an IG vehicle and the Guard looted it right back. This model is one of the ugliest things that Games Workshop has released since the Dreadknight or the Centurions. Consider taking a jeep, and ripping the wheels out to replace them with mini treads which appear to have been based on the Tucker Sno-Cat, except with stupidity in place of awesome all-terrain capability. And then make the thing as tall as a fucking tank, thanks to those same treads being ridiculously tall. The Taurox takes the METAL BAWKSES to their retarded extreme. It also has exhaust pipes going straight into the crew compartment, so your soldiers can sniff some petrol fumes before doing battle (Scions, fortunately, equip themselves with a "respmask array", so they may have designed the Taurox with the Tempestus crew in mind), and then get killed as they disembark by the side-mounted guns which shoot past the doors (Well, there's always the rear hatch, and - if the Imperium's tech-priests had any sense - safeties may have been installed to prevent the side mounted weapons from firing at any time the side doors open). The exhaust pipes exit the cab just above them.
The Taurox takes its design cues from real life MRAP (Mine Resistant Ambush Protected) vehicles. These APCs are built to withstand IEDs and landmines, and to protect passengers from injury during rollovers, which are more common due to the design- idiotically tall. Think a heavily armored Humvee upgrade that can withstand rocket strikes. The Taurox, on the other hand, seems built to kill its passengers. The aforementioned treads are horribly vulnerable to mines, and its relatively low armor rating means that heavier guns (and probably the mines that an MRAP would stop) will pop the Taurox like a balloon.
Oh and if you think it would look better with wheels, it does. Oh so much. A good conversion kit can be bought here[1] or here[2]
Both variants should have side armour 11 to help differentiate them more from the Chimera, and would thus give them a better drive by role.
Patterns
There are two variants of the Taurox. The Taurox and the Stormtrooper exclusive Taurox Prime.
Taurox
This is available to the regular guard. A vehicle that looks a lot like an ork truck and is basically a big Metal Box on top of four smaller Metal Boxes. The Taurox and the Chimera are both the same type of unit (a dedicated Transport) and are used by Imperial Guard squads. The Taurox has a twin-linked Autocannon and lets you re-roll dangerous terrain tests as standard (you will have to buy a dozer-blade to do that for the Chimera) while the Chimera is an Amphibious vehicle (not that that really makes much difference), is a tank, and can weather slightly more hits. This means that the Chimera is better for short ranged guard since it's less likely to get destroyed as it rushes towards the enemy. The Taurox is much better for supporting a shooty Imperial Guard army since a twin-linked Autocannon will deal more damage than a Multilaser will and will do so at less of a cost then a Chimera. Hint: Keep it cheap and have it cover hop. With the re-rolls it can keep mobile and the cover will hopefully keep it alive longer (maybe give it camo netting to take full advantage of this).
Taurox Prime
This is only available to the Stormtroopers. It's basically a version of the Taurox with a Hot-shot volley gun in place of the Autocannons (you can swap back to the Autocannon for free, of course) and a Taurox Battle Cannon. The Battle Cannon on the Taurox is a mini version of the Battle Cannon on the Leman Russ; being 48" S7 AP4 Heavy 1, Blast as opposed to the Leman Russ 72" S8 AP3 Ordnance 1, Large Blast. It can be further swapped for a Taurox Gatling Cannon (another mini version of a present weapon, this one having half the shots of a Punisher Gatling Cannon and being Strength 4) or a Taurox Missile Launcher which is basically the Typhoon Missile Launcher Land Speeders get. In addition, it's manned by Stormtroopers instead of the regular Guard so it has BS 4 instead of 3 and is a Fast vehicle.
The best gun loadout is probably the hot-shot volley gun and the gatling gun; you get 14 S4 twin-linked BS4 shots at 24", which the vehicle can close to with ease; excellent for anti-infantry duty while the troops inside toss melta blasts at anything bigger. The autocannons and Battle cannon are better against light vehicles, but unlike the Chimera, the Taurox Prime doesn't have the toughness to duel enemy armor; it's better suited to lightning-fast strikes against infantry and other soft targets. The Missile Launcher can give the Taurox Prime the ability to punch out of its weight class, but it's 30 points.
You might think this is overpriced, and in comparison to the quality of other Guard vehicles, it is; taking the missile launcher puts you at 110 points, 10 points less than a Leman Russ Eradicator, at a fraction of the survivability and arguably the same firepower. But the truth is that the Taurox Prime is really just average; it's a bit pricey, but it's a Fast Transport, it gets the effect of a Dozer Blade for free, and it comes with more firepower than a Chimera. The ugly track pods will make new players mistake the Taurox for a tank, and it isn't; like the Chimera, it's an AFV, and one that's sacrificed armor for speed and firepower.
Better Alternatives
Much like every other retarded new model, GW has a habit of coming up with rules that makes you feel like you pretty much have to buy the damn things no matter how shit the models are. Well there is another way - We all want twin linked auto cannons so just convert them on to your chimera. Same for the prime, just find appropriate guns for the turret and that'll do it. No retarded box on boxes, just sweet looking chimeras with some heavy firepower.
Alternatively, just find a 1/35 Tamiya halftrack (M3 or Hanomag, depending on your preference) and stick the twin-lined autocannons on it. That way it differentiates itself from the actual Chimeras in your army, and is relatively low-profile in comparison to the actual Taurox itself.
A third option, and the one you'll probably end up going for if you play at GW stores that frown upon 3rd-party models and kitbashes that are significantly departed from the shape of the original model (important for TLOS; the Chimera is shorter, longer, and wider than the Taurox), is to simply not use those idiotic track pods and put some big ol' wheels on it. A few kits exist to convert the Taurox to something more resembling the MRAP it's inspired by (see above); if you happen to like the armored suspension that the vehicle came with (it does kinda appeal in its own way, doesn't it?), it can be fitted to 27mm wheels without much pain.
A fourth option is to use a Genestealer Cults Goliath Truck, which has the benefit of identical stats, wargear, and transport capacity for a perfect WYSIWYG count as match.
In Warhammer Fantasy
In a not-too-uncommon case of repetition, Games Workshop already used the term for Fantasy: 'Taurox' originally appeared in Warhammer Fantasy as a special character for the Beastmen.
Taurox the Brass Bull is a psychopathic Doombull blessed by Khorne for his prodigious talents at killing, having made it a habit of killing and eating anyone and anything that looked him the eye.
Eventually, Khorne took notice and sent one of is Heralds to offer a boon to him - remember, in this edition, beastmen are basically the Chaos Gods' unwanted bastard children and pretty much never get anything nice, in contrast to humans, so that shows how good Taurox was at getting shit done.
Of course, remember what we said about that little habit of his? Yeah; when the daemon addressed him, the dumb brute bit its head off! Then he went into a berserk frenzy, rampaging across the Empire for a year and a day without rest, killing everything he encountered. When the frenzy was finally ended, his whole body had turned into living brass and he was wielding two axes that burned with hellfire.
Except his throat was still living flesh, because you do not bite off a daemon's head and get away with it!
On the tabletop, this manifested as him having a 1+ armour save and 5 wounds, but if you roll 6s for your To Hit and To Wound rolls, then you automatically killed him dead IF he failed that 1+ armour save of his, no matter how many wounds he had left (and unless he's fighting a special character this would nearly never happen).
Taurox was killed during The End Times, when Huntsmarshal Markus Wulfhart put an arrow in his throat from a couple of hundred meters away during the battle for Altdorf.