The Su-27 Flanker and Mig-29 Fulcrum were both late Soviet era designs intended to serve and fight alongside each other versus NATO aircraft in a third World War which thankfully never happened.

Exact numbers for Russia's Sukhoi fleet vary, but there seems to be a consensus that Russia has more than 300 Su-27, Su-30, ...

The most infamous Soviet-era fighters are arguably the Sukhoi Su-27 and the Mikoyan-Gurevich MiG-29 and MiG-25.