Cheapest priced copy (Betrayers of Kamigawa): $0.99 at Card Kingdom, near mint, their price list as of .
Mannichi, the Fevered Dream 
Legendary Creature — Spirit · 1/2 · Rare · The List · #BOK-112
{1}{R}: Switch each creature's power and toughness until end of turn.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $0.99 to $4.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Betrayers of Kamigawa | 112 | Rare | $0.99 | $4.49 |
| The List | BOK-112 | Rare | — | — |
3 rulings from Wizards of the Coast
- 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 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.
- 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.