Boom Bow (look at description) by kitotek

gives a power 10 exploding bow and sets up the commands

to activate the command you must make this setup* and put the command into the command block

*place a command block then place an activator rail on top of it, then, to the west place a block with a Redstone block on top then power the command block and   BAM you have a boom bow

Note: don't minify the command because it causes issues