I was always amazed with Sovyet's tech. Particularly MiG 31.
I know that Foxhound can reach Mach 3.2 and was built to intercept SR71 or the bomber Valkyrie which never entered service.
When SR71 retired, I thought same fate will befall MiG 31, since there's nomore target and it is sluggish with handling tight turns, rendering it unsuitable for dogfight. I didn't know that it packs impressive radar for an interceptor.
This allowed each Foxhound unprecedented detection capabilities—they can spot as many as 24 individual objects at a range of 200 km and track eight of them simultaneously, while the onboard computer determines the four most threatening pings and automatically locks R-33 long-range air-to-air missiles onto them. The four that the MiG doesn't destroy are then immediately targeted by anti-aircraft fire and Soviet fighter jets, thanks to the MiG automatically relaying their coordinates to HQ.