Gordian III & Serapis AE27 Pentassarion of Dionysopolis, Moesia Inferior. 

Obv: AVT K M ANT GORDIANOC AVG, confronted busts  
Rev: DIONVCOPOLEITON, Zeus seated left holding patera & sceptre, E to left. From the Ancient Coins Canada eBay store, buy-it-now of $15, December, 2006.
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