Hint: His rebellion led to the incumbent emperor being murdered by his own troops. As emperor, he would meet the same fate with the approach of his successor's legions.
Guess this thread needs a bump and another clue to keep it rolling. Didn't think this one would be that hard! Clue: he is one of a handful of emperors who reigned for about 3 months. The pic again for covenience:
Tiberius it is. It is also fourree and one of the last Augustus types before Tiberius became emperor. My photo show Tiberius on the left but I guess that really is the reverse. The legend TI CAESAR AVG F TR POT XV. shows he was not yet Augustus but only filius.
The reason I guessed it is due to this Tiberius I just picked up. There is a definite similarity in that Roman nose. Although not quite as drastic as Nerva's it's still quite distinctive.
Note that Race's as is from the same date as the denarius. Tiberius is listed as TI CAESAR AVGVST F IMPERAT.