Rule 208.1 · Power/Toughness

A creature card has two numbers separated by a slash printed in its lower right corner. The first number is its power (the amount of damage it deals in combat); the second is its toughness (the amount of damage needed to destroy it). For example, 2/3 means the object has power 2 and toughness 3. Power and toughness can be modified or set to particular values by effects.

Other rules in this chapter

Ask the judge Pro

The life counter has an AI judge that answers your play citing the exact rules. It is part of Gatewatch Pro; the rules, Oracle text and rulings stay free.