A monster usually dies or is destroyed when it drops to 0 hit points. For more on hit points, see the Player's Handbook.

A monster's hit points are presented both as a die expression and as an average number. For example, a monster with 2d8 hit points has 9 hit points on average (2 × 4 1/2).

A monster's size determines the die used to calculate its hit points, as shown in the Hit Dice by Size table.