Bukkit

Made it so that magma cubes and slimes randomly spawn on the player

I made it so that when a mob dies it has a chance of duplicating

I made it so that damage randomly reverses when I attack an entity

I made it so that invincible mobs randomly spawn on us

I coded it so that placing blocks randomly hurt us

I coded it so that potions randomly rain on us

Minecraft but the Wither is constantly hunting us

I coded it so that screaming Goats randomly spawn on us, and if you stop moving for a few seconds Goats maybe ram into you.

I coded a Minecraft plugin where a wormhole is chasing after us.

Nether mobs are hunting us while we trying and beat the game

Lightning randomly strikes the player and around the player

Any entity that dies has a random chance of exploding