destroyer:
/execute @p ~ ~ ~ fill ~1 ~2 ~1 ~-1 ~0 ~-1 air

(make sure use command block and then choose repeat and always active)

maker
/execute @p ~ ~ ~ fill ~1 ~-1 ~1 ~-1 ~-1 ~-1 grass

(command block same as the destroyer...)
----------------------------------------------------------------------------------------------------
Hope you Guys enjoy it :D