Drill Dozer is a platformer video game developed by Game Freak and published by Nintendo for the Game Boy Advance (GBA). Directed by Ken Sugimori, the game stars Jill and her mech Drill Dozer, which has a drill that the player can rotate in both directions to fight enemies, drill into certain surfaces, and screw objects. Sugimori aimed to make an action game that does not use traditional types of combat, and was inspired by the concept of a tokusatsu monster who could drill through anything. He also wished to make the drill not just pushing a button, but instead using one of two buttons to activate the drill (either drilling forward or in reverse). When drilling, the built-in rumble pack will activate, a feature suggested by Nintendo.

Sugimori wanted to make the protagonist a little girl, as he felt it would be more unusual than a larger male character piloting the mech. Artist Hironobu Yoshida, who struggled when drawing female characters, found her difficult to design, but managed to make progress when he was inspired to design her hair after roll cakes, having his wife hold one on either side of her head. The game was released on September 22, 2005, in Japan, and on February 6, 2006, in North America. It was initially unreleased in Europe, only arriving there upon being released on the Wii U's Virtual Console in all three regions in 2016.

Drill Dozer has been generally well received, regarded as one of the best GBA games by multiple writers. Its level design and drill-focused gameplay was particularly well-received, credited as being unique and setting it apart from other platformers. The music's reception was more mixed; while some enjoyed it, others found it repetitive. The game ended up being a commercial failure, attributed by multiple authors to it coinciding with the Nintendo DS release and poor marketing. This led it to being viewed as a hidden gem.

Drill Dozer is a 2D side-scrolling action-platformer where the player controls the protagonist Jill, who pilots a mech called a Drill Dozer. The player uses the Game Boy Advance (GBA) shoulder buttons to control the direction of the drill, with one button drilling clockwise and the other counter-clockwise. When the drill is used, a user interface appears and the built-in rumble pack activates. This is used for different functions, including tightening or untightening screws, destroying blocks, and fighting enemies. These blocks have different functions; while some vary only by thickness, others have their own mechanics, such as jelly blocks, which can be used to jump backwards off of them to reach a platform. The drill can also be used to drill through tunnels, using the two buttons to go forward or backwards. Certain objects will be color coded, communicating whether they require the drill to work forward or in reverse.

The game spans more than a dozen levels featuring blocks, enemies, and environmental obstacles. At some points during each level, Jill is ambushed, and the player is required to beat multiple enemies before proceeding. As the player progresses in each level, they can find sprockets that, once collected, allow the player to shift up to the next gear, done by pushing the respective shoulder button when prompted. This allows Jill to drill through harder blocks or continue drilling for longer. When finding the second sprocket in the level, the player is now able to drill indefinitely. Once the level is complete, the Drill Dozer loses these sprockets, requiring them to be collected in the next level. Throughout the level, the player collects a currency that can be spent at a shop in the game's main menu on different items, including health tanks, special drill bits, and maps to unlock bonus levels. These drill bits are capable of destroying blocks that were previously unable to be destroyed.

In some levels, the Drill Dozer is able to use a special upgrade that lets it fly or traverse bodies of water. At the end of each level, the player faces off against a boss that is battled with the drill. In addition to playing through the levels, the player is tasked with increasing Jill's reputation as a thief, which is accomplished by collecting treasures across the levels. Upon beating the game, an increased difficulty mode is unlocked.

Drill Dozer follows a young girl named Jill, the daughter of the leader of a bandit gang known as the Red Dozers. Her father was ambushed by a rival gang known as the Skullkers, stealing a Red Diamond that belonged to Jill's mother, leading Jill to mount a mech called a Drill Dozer to retrieve it and defeat the Skullkers. Along the way, she finds four other diamonds, which affected the behavior of people and objects, such as the Dark Diamond, which gave Crooge, the alien-like leader of the Skullkers his power. Once Jill destroys the Dark Diamond, Croog's alien face falls off and he runs away crying. Jill recovers the Red Diamond and is appointed as the new boss of the Red Dozers by her father.

Drill Dozer was developed by Game Freak and directed by Ken Sugimori, the first game he directed since Pulseman in 1994, approximately 11 years prior. Development began after Pokémon Ruby and Sapphire, while Pokémon Emerald, an upgraded version of Ruby and Sapphire, and Pokémon FireRed and LeafGreen, remakes of Pokémon Red and Green, were in development. Sugimori stated that because they were upgrade versions, they required less staff to work on them, and thus had the opportunity to work on something else. He was also inspired to begin production due to staff's interest in creating a non-Pokémon game, particularly an action-based one. Sugimori stated that he was concerned about the professional development of Game Freak staff who have only worked on Pokémon games prior to this; in turn, he focused on doing art for the game, while most of the gameplay and programming was handled by younger staff members. Development started with around 4-5 staff members.