20 Paisa - Habibullah Kalakani

Habibullah Kalakani — known to his opponents as Bacha-e Saqao, "son of a water carrier" — seized Kabul in January 1929 after Amanullah Khan's reformist government collapsed under tribal revolt. His reign lasted nine months before Nadir Khan's forces retook the capital and had him executed in November of the same year. Coins struck in his name are among the rarest of 20th-century Afghan issues by simple virtue of that compressed timeline.