I say the Heat-Knicks rivalry.
In the 1990s they had everything from buzzer beating shots and close games to brawls, and coaches hanging on players legs(Knicks coach Jeff Van Gundy on Heat C Alonzo Mourning).
The Heat and Knicks seemingly played in the playoffs every year and you knew it would be intense every time they stepped on the court against each other.
Its a rivalry I miss alot
If you could bring any "old or dead" NBA rivalry back which one would you bring back?