As of creation, there has not been a confirmed T-14 used in combat

https://en.wikipedia.org/wiki/T-14_Armata

The T-14 Armata (Russian: Т-14 «Армата»; industrial designation Russian: Объект 148, romanized: Obyekt 148, lit. 'Object 148') is a Russian fourth-generation main battle tank (MBT) based on the Armata Universal Combat Platform.

The Russian Army initially planned to acquire 2,300 T-14s between 2015 and 2020.[13][14][15] By 2018, production and fiscal shortfalls delayed this to 2025,[16] before Russia announced the apparent cancellation of the main production run on 30 July 2018.[17] However, as of 2021, the Russian state-owned TASS media agency claimed the Armata had been expected to begin serial production in 2022, with delivery of a test batch of 100 to the 2nd Guards Tamanskaya Motor Rifle Division expected to begin in 2022.[18] The tanks are planned to only be officially transferred following completion of all state tests.[19][20][21][22] In December 2021 the Russian state conglomerate Rostec stated that serial production had commenced,[5] with "more than 40" Armata tanks anticipated to be delivered to Russian troops after 2023.[23] On 4 March 2024, Sergey Chemezov, the CEO of Rostec, stated that the T-14 Armata had entered service with the Russian Armed Forces.[24]