Cheapest priced copy (The List): $0.35 at Card Kingdom, near mint, their price list as of .
About Face 
Instant · Common · Urza's Legacy · #73
Switch target creature's power and toughness until end of turn.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
2 printings · $0.35 to $4.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| The List | ULG-73 | Common | $0.35 | — |
| Urza's Legacy | 73 | Common | $0.35 | $4.99 |
4 rulings from Wizards of the Coast
- 1 November 2005Note that the wording "Effects that alter the creature's power alter its toughness instead, and vice versa, this turn" has been removed.
- 19 March 2021Switching 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.
- 19 March 2021Effects 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.
- 19 March 2021Because 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.