The year is 2055, more than thirty years after the events of Zero Hour, Earth suffers a catastrophic collision with meteorites. The world is thrown into turmoil as large swathes of land are annihilated. Four factions, the ADF (Asian Democratic Federation), WEA (West European Alliance), WLF (World Liberation Front), and AC (American Confederacy) are at war for control of the remaining already harder to find resources as well as the preservation of their nations and geopolitical interests. Welcome to Deep Impact.
*Disclaimer: As a support weapon, the Engineer modification is not always deemed necessary by higher-ranking officers looking to capitalise on the MRC's military benefit, and thus is often not shown in material designed to attract military attention - the Engineer modification is seen simply as a small bonus. Since then, the Engineer has shown its true worth in battlefield situations, as detailed below.
The Engineer modification is even more self-explanatory than the Railgun. The Engineer modification allows the MRC it’s greatest support role, letting it repair damaged vehicles on the battlefield. By lowering the thrust of the electrostatic pads, the MRC can hover just above vehicles and perform repairs, without damaging the armour in the process (as would the other MRC variants). The MRC again keeps its original chain gun, so that it is not defenceless, but as a support platform, the Engineer MRC rarely tends to venture out alone. Instead, combined with an assault force, the MRC can protect those all-important assets from perishing in battle, instead leaving the enemy to wonder how your forces just keep coming.
To summarise, you cannot do without the MRC. Its versatility, speed, and presence on the battlefield is one of great encouragement to any commander. It is also something that any enemy should fear, as an MRC without any modifications applied can become, in seconds, capable of hitting the enemy exactly where it hurts, or assisting the attacking troops, also exactly where it hurts.