|“||Bureaucratic doves, 'bout damn time!
- Havoc's response to production of the Mastodon at the reopened San Pedro war factory in 2069, 
- Main article: AW-12 Mastodon/Profile
The Mastodon eschews its predecessor's large experimental railguns for an equally deadly, but also less expensive, chin-mounted "Tusk" artillery battery. The battery can fire four sonic shells in rapid succession to destroy masses of targets in its line of fire, achieving a similar effect to the railguns. The reduced cost allows multiple Mastodons to be deployed simultaneously in a given area. Groups of Mastodons are referred to as "herds". The Mastodon's legs are also armored against their own Dispersion Bays' flechette shrapnel.
Its secondary armament consists of a pair of anti-surface/anti-air missile launchers and the Depth Charge Emergency Ejection System. The Depth Charge system dropped explosive charges from the walker's flanks to repel close-quarter assaults—whilst causing no damage to the Mastodon, compensating for the artillery battery's forward-only firing arc. The "Depth Charge" system was a later development and were still being retrofitted to older production units at the time of the Fourth Tiberium War.
The Mastodon Backup System is a Nod-derived nanotech repair module. The module activates after the walker suffers catastrophic system failure and slowly repairs the vehicle; the module can eventually bring a Mastodon back online to full strength if an engineer is unavailable.
|“||What? Return fire!!
- Mastodon operator, Tiberian Twilight
Although the Mammoth Mk. II walker was decommissioned after the Second Tiberium War, support for the concept survived and was reinforced by the Third Tiberium War. Despite considerations of future Scrin invasions, funding was not available at the time to revive the walker. The debate reignited with increased military funding once construction of the Tiberium Control Network was well under way. The GDI Council of Directors ended the heated argument between the generals; it authorized the production of both a new Mammoth tank and a next-generation Mammoth walker to cover anti-Scrin contingencies.
A redesign of the Mammoth Mk. II resulted in the Mastodon. Improved technology bestowed the Mastodon advanced lighter armor that confers superior resilience and mobility compared to its predecessor: the Mammoth Mk. II, whilst still being significantly less expensive to deploy—some of the these improvements were based on innovations Kane derived from the Tacitus. The first Mastodon emerged from the renovated San Pedro war factory in 2069, the same factory where the last Mammoth Mk. II had emerged 30 years earlier.
Early abortive Mastodon prototypes were created before the 2062 alliance at the El Paso base in Central America. They saw combat when Nod invaded their base with prototype Widows and managed to push back the invaders.
There are husks that can be found in these missions:
- There are two husks in the mission "Transport Down" one near in the refueling station, guarded by visceroids and scrapbuses, then another one in the upper left before the TCN hub, thistime guarded by ironbacks and visceroids.
- There is a husk before the refueling station, in the Nod mission "Things Fall Apart"
- There are two husks, one downside left in the mission "Cold Hard Truth," the other up near the northern Nod deployment zone (the lower one is not present on hard difficulty).
- Two husks can be found in "Lockdown" outside the facility on the eastern side.
- There is a husk on the ridge just northwest of the starting point in "For All Humanity."
Virtually identical in appearance to the Mammoth Mk. II, the Mastodon lacks several components that would truly make it a twin to the Second Tiberium War leviathan. Aside from the Mammoth Mk. II's quadrupedal profile, the Mastodon is different in every other conceivable way.
At first glance, one would think that it is the Mammoth Mk. II reborn. But closer inspection will reveal that, unlike the Mammoth Mk. II, as well as being less bulky and more mobile—the Mastodon does not have the large side-mounted experimental railgun pods. Instead, it has a large artillery battery mounted under the cockpit and a pair of multipurpose sonic missile launchers on the rear of the fuselage. The advanced rocket battery—whilst just as powerful, if not moreso deadly against masses of lighter enemies, is an armament that is not quite as sufficient for taking on heavier armored vehicles. And as a form of artillery: it is only useful up to a certain proximity, beyond which it is rendered useless.
This disadvantage was noted by GDI engineers however, and is balanced with the addition of the Dispersion Bays, which are small slots that are added to the outer hull. From these slots, small but powerful explosives are automatically fired upon units foolish enough to get too close to the Mastodon. Whilst these explosives do not detonate upon impact, they detonate with deadly force, especially against infantry and light attack vehicles. And whilst the Mastodon's own superior armor is immune to the explosives themselves, the same cannot be said for the enemies being bombarded below.
Another key feature that sets the Mastodon apart from the Mammoth Mk. II is its significantly improved resilience. As well as possessing advanced next-generation lightweight armor that's even tougher than the Mk. II's own plating, it can be upgraded with specialized Backup Systems. Once the Mastodon has taken critical damage and is no longer able to function, the husk it leaves behind will very slowly start to repair itself. Provided the husk isn't captured or destroyed in the meantime, the Mastodon will continue to repair itself to full health, giving it a "second wind" and the ability to deal out even more damage with a surprise attack any inexperienced enemy commander would never expect.
- Artillery platform operative.
- Operating at full capacity.
- Mastodon, fully armed.
- Mastodon at the ready.
- A pleasant day for an assault!
- Awaiting plan.
- Reactors, online.
- All stations standing by.
- Where are they hiding?
- Turbines to full power.
- Push forward.
- A sound order.
- I concur.
- Mastodon en route.
- Crush them!
- Put that one down!
- Fire all weapons!
- Give them a taste...
- Flatten them!
- Eliminate it!
- Main turret!
Move to Attack
- Weapons, get ready!
- Gunners, to your post!
- Pathetic scum!
- Prepare to engage!
- Fire on my command!
- All targets shall be neutralized!
- Mastodon has restored full power.
- Mastodon reactivated!
- Mastodon restored and ready.
- They don't stand a chance!
- Elimination in progress.
- Almost there...
- Keep firing!
- Finish them!
- Every last one of them...
- We must quell this annoyance!
- This little uprising won't go unnoticed!
- What?! Return fire!
- Let them do their worst!
- Cocky little buggers, aren't they?
- Mastodon is taking fire!
- Altering assault plan.
- Regroup at the Crawler!
- Destroy anything that follows.
- The Mastodon bears some similarities to its much less powerful cousin, the Striker.
Both seem to be based on Star Wars machines; the Mastodon looks similar to the AT-AT (All Terrain Assault Transport) and the Striker bears several similarities to the AT-ST (All Terrain Scout Transport). As well as this, both have the stereotypical upperclass British voice, and both belong to the GDI Offense class.
When left idle, the Mastodon will crouch down on its forelegs like a dog.