Dolyen (ドルエン,Doruen, combination of dollar and yen) is the galactic currency used by the Galactic Imperial Army Zone, the budget of which is managed by Galactic Merchant Dongoros. It is said to be equal to 100 Japanese yens or around US $.066(the actual exchange rate between the Japanese Yen and the US dollars during the show's initial run in 1990). It was revealed in episode 26 that they also have an upside down day wherein Garoa and the triumvirate are under the authority of the Batzler Soldiers and as well as a Silver Imperial Army Monster.
Land Gamma was disabled by a 10,000,000 dolyen land mine, which mostly came from Dongoros' personal stash. In return, Dongoros' requested a reward 100,000,000 dolyen from Captain Garoa after the destruction of Earth but was swiftly rejected, Garoa disgusted at his greed. He bribed Sairagin with a paltry 5 dolyen. Ep. 7: The 45m Grade-Schooler
Dongoros employed Butarugin, a porcine Galactic Warrior who inhaled and counted money through his snout, with 100,000 dolyen. Insisting on another 100,000 to defeat the Fivemen, upon seeing Dongoros' stash, however, Butarugin was overwhelmed with greed and blew out the lot. Ep. 18: Saving Money!!