Below is a photo of an Otho denarius. It is probably the most common Otho denarius one can find for sale. Still, like all coins of Otho there is quite a bit of competition for them when they appear for sale. What I like about this one is the portrait. It is also a bonus that his name is on the flan.
Otho rules for three months in 69 CE and was the second in the year of the 4 emperors. He committed suicide rather than subject the empire to useless bloodshed.
Otho AR Denarius. Rome Mint. ( 17.89 mm, 3.08 g)
Obv: IMP M OTHO CAESAR AVG TR P, bewigged head right