Good question! The answer is: Whichever one hits the field first will cancel out the other Body. If there is an Active Aggron ex in play, if the opponent plays a Dialga G LV.X Time Crystal cannot be used. Conversely, if the Dialga hit the field before the Aggron, Intimidating Armor can't be used.
OR, if Aggron hit the field first, but then left the active spot, Intimidating Armor shuts off, and stays off until the Dialga leaves the field. When Armor shuts off, DGX can use Time Crystal again...and that will stay on regardless of where on the field DGX is.
