Mini Bombs are tiny sticks of dynamite that have less power than normal dynamite, but can be used in close range. Gokudera generally uses this when he's in need of a speed burst (he does this by flicking the dynamite behind him) or when the enemy is too close to use normal dynamite. Gokudera also uses this dynamite to perform combos with his larger dynamite sticks. In this case he uses the smaller dynamite as a visual trick.