Live boky reaction

/summon ender_dragon with a repeating command block and a lever
/kill @e with another repeating command block and a lever
activate both of them at once
your computer will thank me from heaven

I already have a contraption like that

My phone got so hot my hands were sweating

LMAO
I remember doing that exact setup and seeing the light of god

It's even worse if you do it with slimes and iron golem together