Crag Puca — ruling 1

Effects that switch a creature's power and toughness apply after all other effects, regardless of when those effects began to apply. For instance, if you target a 1/2 creature then give it +2/+0 later in the turn, it's a 2/3 creature, not a 4/1 creature.

Crag Puca — ruling 2

Because damage remains marked on a creature until the damage is removed as the turn ends, nonlethal damage dealt to a creature may become lethal if you switch its power and toughness during that turn.

Crag Puca — ruling 3

Switching a creature's power and toughness twice (or any even number of times) effectively returns the creature to the power and toughness it had before any switches.

Crag Puca : règles, fonctionnement et interactions (MTG)

Crag Puca is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

: Switch this creature's power and toughness until end of turn.

How it works : Crag Puca

Original English text — Wizards of the Coast / Scryfall

#1March 19, 2021· Wizards of the Coast
Effects that switch a creature's power and toughness apply after all other effects, regardless of when those effects began to apply. For instance, if you target a 1/2 creature then give it +2/+0 later in the turn, it's a 2/3 creature, not a 4/1 creature.
No other card is named in this ruling.
#2March 19, 2021· Wizards of the Coast
Because damage remains marked on a creature until the damage is removed as the turn ends, nonlethal damage dealt to a creature may become lethal if you switch its power and toughness during that turn.
No other card is named in this ruling.
#3March 19, 2021· Wizards of the Coast
Switching a creature's power and toughness twice (or any even number of times) effectively returns the creature to the power and toughness it had before any switches.
No other card is named in this ruling.