Edison Format · March 2010
The effect of "Shield Warrior" is a Quick Effect. Removing "Shield Warrior" from play is a cost. This effect does not target.
You cannot activate the effect of "Shield Warrior" if your monster would not be destroyed by the battle.
If a monster you control is forced to battle another monster you control by the effect of your opponent's "Ancient Lamp", when you activate the effect of "Shield Warrior" during damage calculation, both of your monsters are not destroyed.