Minecraft fireball or lightning sword?

I got a friend on Minecraft a few months ago. Then he told me that I can come to his server. After a couple of hours, he executed a command to make fireballs and lightning bolts etc. With an object in his hand (in this case the sword) and now I wanted to try that again but I forgot the command. Does anyone know what the command is called?

You may need a plugin for this

Google times. The command will be endless, too much to memorize.