The Strv 122B+ is a testing bench and technology demonstration unit for improved protection on existing Strv 122 units. The proposed prototype was to be produced around 2010-2011 and form part of a modernization programme for the Strv 122. The Strv 122B+ was designed to improve protection against threats in urban combats and got additional protection against different type of explosive threats that can be lethal for an vehicle in urban situations and close combat. However, these additional protection kits were never put in the modernization of the Strv 122s.
The Strv 122B+ was introduced in Update "Air Superiority" as a new top tier MBT for Sweden, coming with improved protection against chemical rounds and shaped charged ATGMs bolstering the survivability of the vehicle. Still having the same 120 mm L/44 gun compared to the Leopard 2A6 and Leopard 2A7V with their 120 mm L/55, it would seem the Strv 122B+ is inferior in terms of firepower and penetration, but this is not an issue for it due to it still being competitive at top tier. Even with additional armour, the Strv 122B+ is still highly manoeuvrable with its additional weight and doesn't affect the speed at all. The Strv 122B+ still has vulnerable areas on the hull against kinetic rounds and, like its predecessors, excels in a hull-down playstyle, exposing only the well armoured and protected turret to peek out and fire at enemy units. Angling the armour of the hull with the additional armour gives it better chance to survive close combat engagements than other Leopard 2s.