with your object try different Effects like bulge,Sphere, warp, (in the left panel when object is selected under Behaviors ) then keep witchever one you like and add the event
condition: is touching(if using mouse event mouse touching ) object
action set whatever effect you pick enabled
then new event (hit X)
condition: Else
action:set effect disabled
'
hope this helps
there are more ways to do this as well you could change animation frames when touched which it petty much done the same just change the event to changes frame and not whether effect is enabled