There are four minigames hidden within the Normal Game. Each one, when cleared, awards you with a Bomb Merge Item that you need to build new Attribute Bombs later on.
If you can find all the Charaboms, a "Mini Games" option will appear on the title screen, where you can access all the minigames.
Bomjy Jump[edit]
Location: 1-1
You start out floating 40m above the ground on a leaf with the camera pointed down towards a river on the ground and a one-minute clock. Once the clock starts, the leaf will slowly drift down. Meanwhile, logs will periodically float along the river below. When you press 
, you'll jump off the leaf. While falling, you can tap as needed to slow your descent slightly. Your goal is to time your fall so as land on one of the logs and avoid ending up in the river.
Clearing Bomjy Jump in the Normal Game awards you the Water Balloon, which you need to create Aqua Bombs.
MotorBomber[edit]
Location: 2-4
You have 25 seconds to speed down a straight icy course on the MotorBomber. The course, however, is littered with icy roadblocks you must work around. Holding will accelerate the MotorBomber, and you steer around ice using the Control Stick. However, your steering is limited while you're accelerating, so letting go of is recommended to steer around the ice; you can then resume accelerating. Cross the finish line before time runs out to clear the game.
Clearing MotorBomber in the Normal Game awards you Shaved Ice, which you need to create Ice Bombs.
Bomber Marathon[edit]
Location: 3-4
You are running around a circular track trying both to outrun a boulder and unlock the path into the center goal area. To run, you must tap 
repeatedly, but the boulder can easily outrace you. To buy time, you must step on the green switch. This releases a Bomb icon on the track, which when collected enables you to drop one bomb behind you by pressing . When the boulder hits the bomb, it'll be delayed, giving you a chance to loop around the track to hit the green switch again and get another bomb. But you must watch out for stones scattered around the track. They'll stop you cold while the boulder crushes them without slowing down. To actually clear the game, you must drop a bomb on a yellow switch on the track and then, while the bomb's still there, run through the open gate to the center.
Clearing Bomber Marathon in the Normal Game awards you the Fan, which you need to create Wind Bombs.
Rail Bomber[edit]
Location: 4-1
You are moving along a track in a mine car. Ahead of you are a series of obstacles: boulders that block your way and switches that will divert you off the track. Holding the control stick forward will accelerate the car. Pressing will make you throw a bomb ahead of you, but be careful as a careless throw or headlong rush can cause you to be knocked off by your own explosions. Boulders will be destroyed if a bomb blows in front of it, but if a bomb hits the boulder itself, it'll be deflected harmlessly away. Detonating a bomb next to a switch will redirect the track in the right direction, but only temporarily. You must speed through before it switches back. You must get through the entire course without being divered off the course or crashing into boulders or your own explosions to clear the minigame.
Clearing Rail Bomber in the Normal Game awards you the Strobe, which you need to create Light Bombs.