How did otus and ephialtes anger Zeus?

Otus and Ephialtes, the giant sons of Poseidon, angered Zeus by their audacious attempt to overthrow the gods. They kidnapped and imprisoned Ares, the God of War, and sought to stack mountains on top of each other to reach the heavens and wage war against the deities. Their arrogance and defiance of divine order ultimately led to their downfall when Zeus sent Artemis to deceive and slay them, highlighting the consequences of challenging the supremacy of the gods.