Tetricus, barbaric imitation from reversed dies.

Garbled legend for IMP C TETRICVS PF AVG, radiate, draped bust left.
Garbled INVICTVS, Sol walking right, holding whip, left hand raised. 
(On the original coin, the images are reversed)

RIC V-2 234 barb.

Courtesy of Antike Muenzen Auction, 2002.