Out of the many gods in the universe, Beerus is the most feared. He is feared by the Kaios and the Kaioshins. As a God of Destruction, he is tasked with maintaining balance in the universe. Any God of Destruction destroys planets according to his/her own judgment.
Because he is quite capricious, Beerus destroys even important planets without a second thought. When he finds it bothersome, he lets someone else act as an agent of destruction. While he is awake, tense days for the Supreme Kais continue, as nobody knows how many planets will be sacrificed. Seeing that he is based on a cat, he also shares their lazy traits: the times he wakes can variate depending on his mood and there's no telling how many planets he can and will destroy. He is also quite irritable, as if he is even ticked off a little, he will destroy a person's planet for almost no reason at all.
Beerus' physical design also takes some inspiration from Ancient Egyptian deities, notably Seth and Sekhmet. Seth is a humanoid with a jackal-like head who is the god of desert, storms, darkness, evil, strength, winds, war, conflict and chaos in ancient Egyptian culture.
He is actually the God of Destruction of Universe 7 (where the Dragon Ball story takes place) and he revealed that there are 12 Universes in total with beings even stronger than he is and that Whis is his master.
Being a God, he posses immeasurable power, so much so that he can defeat Goku as a Super Saiyan 3 with merely two moves.
Once every 1,000 years, the Supreme Kais and the Gods of Destruction go to each other's realms and hold a coordination meeting. During one of these meetings held roughly 75 Million Before Age, they got into an argument over some trifling thing, and the short-tempered Beerus sealed Old Kai away inside the Z Sword, as it would not have been proper for him to destroy the Sacred World of the Kais itself.
Beerus was also responsible for many different events in Dragon Ball world. He was the one who ordered Frieza to blow up Planet Vegeta. He also blew up Norhern Kaio-sama's planet just because he lost in a game of hide-and-seek. Some time in the past he came to Earth and caused the extinction of the most dinosaurs on planet
Scores of anime characters can level mountains, resurrect the dead, or perform similar feats but few possess the level of power necessary to truly be called a god. From warping reality as they see fit to changing the course of history for fun, these deities can influence whole worlds on a whim.