Publicly

Emptied several bakeries in his territory to feed the bread to a hole in the ground by the roots of a "man eating tree"

Picked up a wide range of beast people (wolves, tigers, cats, a half rat etc.) and dragons and became an unofficial zookeeper

Bought a magic tower for absolutely no reason only to destroy it a year later

Saw dragons turn up at his brother's doorstep and laughed like a maniac

Tried to strangle the prince of another nation with his bare hands

Set one of the most dangerous places on the continent on fire, then put the fire out himself to fill it with water

Bitch slapped the big bad

Beat up the illusion of the big bad with an enchanted pebble

Stabbed himself in the heart with a tree root

Privately

Threw a bunch of money into lava, twice

Blew up an island, twice

Ate a rock to power up, twice

Staged a coup for another nation, twice

Set a historical lake on fire

Set a castle('s surroundings) on fire

Moved the late Dragon Lord's lair to his backyard

Declared war on himself

Cussed out a God, more than just once

Bonus: Choi Han

Together with Rosalyn and Lock has destroyed a palace, twice