Hottaman's no Chitei Tanken ("Hot Man's Underground Exploration") is an action game in which the eponymous Hottaman/Hot Man explores underground using his trusty drill and his flame weapon (hence the name "Hot Man"). The player can discover all manner of items and enemies by digging through each level.
The goal is to find four keys, usually hidden inside containers or dirt, which will reveal the exit to the level a la the original Bomberman. The player can also find a shovel power-up that boosts their speed, items which increase their score, eggs which either contain enemies or items and bombs which destroy certain blocks that Hottaman cannot drill through (as well as any enemies caught in its blast).
Though clearly inspired by Dig Dug, right down to the player character's robotic-looking white hazard suit, the game also aims to expand beyond the classic's smaller scope, adding a lot of extras and making each level suitably enormous. The game was Use Corporation's first foray into development for the NES/Famicom.