Help in Metal Slug 7 ?

hey can anyone help me in mission 3 i was stuck where the big ball chases you >? thanks ;D

 

You need to fire in front of the little box to you start to moving the box to dowm the elevator in your front! do it fast!

 

i tried to shoot the box but it wouldn't budge at all... and i tried bombing it everything

 

i figure it out ;D you'll just need to press the y button and keep pressing it until it works thanks though

 

heh i figured it out u have to walk up to it and press y

 

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