Lightning Tower in minecraft 1.8.4

Lightning Towers in Minecraft Enjoyed:
first Command you needed to the Tower and the other Commands:
to Find Zombies: /testfor @e[type=Zombie,r=28]
to The LightningBolt: /execute @e[type=Zombie,r=26] ~ ~ ~ /summon LightningBolt ~ ~ ~
https://www.youtube.com/watch?v=e42c7-YD4MI to The Video by Command_man Commando