When playing in arcade mode, there is an easy way to get 40 balloons. Start off with the side that has most balloons. And after you lay down a bomb, stand next to it. After it explodes, start pressing A and move around. Since you are invisible, you will be a walking bomb and will get 40 balloons easily.
Block Brainbomber
Bombs can be used to block Brainbomber's lightning strikes, the groundtrail, and the targeting.
Free large Medicine
Equip Kai-man and go under the water. Find a green switch and activate it, then talk to the school of fish. You will get the Fishhook and a Karabom will join you. Take the Fishhook to the fisherman to get the Medicine.
Fusible Transistor
Once you reach Gamma town, go south and kill the two Orkmen. Enter the coliseum and win five matches in a row. You will receive 150 gold and the Fusible Transistor.
Heart
There is a girl in the volcano who wants a T.beef that she will trade for a Heart. She is located below some caves that are close to GLM.Base. In the first forest, there is a movable block. Once you push it, it reveals a staircase. A man will give you a heart. From Delta, go up a screen and head to the Northeast to find another movable block with another person with a heart.
Remote bomb detonation
Once you have Sibaloon, go back to the lake in the first zone. You will be able to find a cottage with Firekong, who allows you to remote detonate your bombs.
Balloons in arcade mode...