If a creature originally has a power of 1 and toughness of 3, and the +0/+1 effect ends before the switching effect, what will the creature's stats be?

To determine the creature's stats in this scenario, it is important to understand how power and toughness modifications work in Magic: The Gathering.

The creature starts with a base power of 1 and toughness of 3. A +0/+1 effect means that the creature will gain one additional toughness, raising its toughness to 4. However, if this effect ends before the switching effect occurs, the creature will revert back to its original toughness of 3.

The switching effect likely refers to the proposal of switching power and toughness, but since the +0/+1 effect expires first, the creature is left with its original power of 1 and the reverted toughness of 3.

Therefore, after the +0/+1 effect ends, and assuming the switching effect does not apply a new modification after the +0/+1 effect has ended, the creature's final stats would be 1 power and 3 toughness. This makes it a 1/3 creature.