The Expeditionary Fighting Vehicle (EFV) was a prototype amphibious assault vehicle (AAV) developed from 1996 to 2011 by General Dynamics for the US Marine Corps to replace the AAV-7A1 as the main AAV for the USMC. The EFV was intended to be a significant improvement over the AAV-7 in every aspect, most notably increased protection, improved armament in the form of the 30 mm Bushmaster autocannon, as well as powerful diesel/water jet engines to significantly increase mobility while on the water. However, due to changes in USMC doctrine from utilising heavily armed AAVs to instead clearing out enemy defences at long range using air and sea bombardment, along with the excessive R&D costs, the EFV was considered unnecessary, and the project as a whole was cancelled in 2011.

Introduced during Update "Tusk Force" as a reward for the 2025 "Semper Fidelis" event, the EFV stands out among other IFVs for its gargantuan hull clad with several layers of composite screens on all but the frontal side, with plenty of internal space. This unusual characteristic allows the EFV to absorb several hits, so long as they do not strike critical compartments. Due to its powerful waterjet engine, the EFV is capable of reaching a top speed of 42 km/h on water—twice or even three times faster than any other amphibious vehicle. This gives the EFV additional tactical mobility across areas that most tanks would otherwise struggle to reach. However, the EFV is "only" armed with a 30 mm autocannon, a weapon that is effective only against other IFVs or in flanking manoeuvres, something that is difficult to pull off unnoticed due to the EFV's huge profile.