Gaurdians are weak....by the time somone techs up that high ud have hightemps or archons wiping out the gaurdians.....the best defensive cabability for toss are cannons .....ive been saved by 2 or more cannons many times in all the games ive played being attacked by mass zergling and zealots....i can survive a mass zeal attack with only 1-2 cannons and of course 2-5 zeals backing them up....Cannons maybe weak when attacked but strong for their attack speed and power....all it needs is backup...