A cool mob killer redstone device. A friend from my art class asked if it's possible, to make a sign saying "Zombies Die" and then press a button and the zombies die, and I said yes. Sadly, zombies burn in sunlight, so I used creepers.
How It Works

1. Press button.
   
2. Power goes through redstone, activating TNT.
   
3. TNT explodes, not destroying bedrock "house", but killing creepers.
   
4. Yay!
   

Hope you liked my project! Please check out my website! theminecraftgirls.weebly.com