I tested it by giving a angry wolf and a zombie strength 100 with this command (not in a command block, but also that doesn't work) /effect @e[type=!Player]
5 10 100
I tested it by giving a angry wolf and a zombie strength 100 with this command (not in a command block, but also that doesn't work) /effect @e[type=!Player]
5 10 100
http://minecraft.gamepedia.com/Potion_of_Strength :