The SPz 12-3 LGS is based on the HS.30, a German Infantry Fighting Vehicle, which was also the first IFV in the world. Unfortunately, being the first in any field has consequences, and the HS.30 was quickly outpaced by first the Soviet Union's BMP-1 and a mere 4 years later (from the SPz 12-3 LGS's deployment) by the Marder family of IFVs in the Bundeswehr. Due to performance shortfalls and a rocky development history, the vehicle's initial 10,680 strong order was drastically slashed to just 2,176 vehicles, of which the SPz 12-3 LGS was a part of. The most notable change from the HS.30 to the SPz 12-3 LGS is the very noticeable 106 mm recoilless rifle that takes up the infantry compartment, which augmented the vehicle's lethality against enemy armoured vehicles with its high-penetration chemical rounds. The SPz 12-3 LGS was produced starting 1965 as a conversion of the HS.30, but all HS.30-derived vehicles were all but retired by the 1980 mark as the Bundeswehr transitioned to the Marder series of IFVs as well as the Raketenjagdpanzer series of tank destroyers in a transition to more effective, reliable vehicles.
The SPz 12-3 LGS was introduced in Update "La Royale" as a reward for Battle Pass: Season XII, "Armour Breaking Ambusher". Equipped with a 20 mm MK20-1 autocannon and a 106 mm M40A1 recoilless rifle, it is able to engage both light and heavy armour effectively with high levels of versatility. While the hull is noticeably more sluggish compared to its upsized brethren such as the JPz 4-5 due to an underpowered engine, it is also a much smaller vehicle and can easily hide the hull behind cover to ambush unsuspecting enemies. However, as the gun depression of the M40A1 is only -6 degrees, the vehicle doesn't have as much flexibility as other 106 mm recoilless rifle carriers at a similar BR, such as the M50 and its -10 degree gun depression. Still, it is enough to utilize most spots on the map by only showing the upper right corner of your hull to fire, greatly increasing your survivability by not being seen in the first place until it's too late. Armour is adequate enough to stop low powered autocannons at range, but any serious enemy fire will easily penetrate your thin armour without much issue, so it's best to use the map to play around this weakness.