How does the mechanic of blocking damage work in Magic: The Gathering (MTG)?

In Magic: The Gathering (MTG), blocking damage works by assigning creatures to block attacking creatures during combat. The blocking creature's power and toughness determine how much damage it can prevent. If the blocking creature's toughness is equal to or greater than the attacking creature's power, it will survive the combat and prevent damage. If the blocking creature's toughness is less than the attacking creature's power, it will be destroyed and the excess damage will be dealt to the defending player or planeswalker.