ISS Gagarin

In the mirror universe, 'ISS Gagarin (') was a Terran Empire starship, a cruiser in Imperial Starfleet service in the 2250s decade. 

Service history
The ISS Gagarin's counterpart from the primary universe was the USS Gagarin (NCC-1309). 

The Gagarin and other Terran Empire cruisers of its class participated in a Terran invasion of Pahvo, travelling from the mirror universe in 2256 to the prime universe in 2410. The fleet was led by the and its sister ships, and ultimately halted by defense satellites and a squadron of Alpha Quadrant Alliance ships. 

In another encounter, the Gagarin and other Terran ships faced off against a Klingon fleet from 2256. ( in-game announcement banner)