Aquamoeba

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

Dominaria Remastered

Discard a card: Switch Aquamoeba's power and toughness until end of turn.

Vintage Masters

World Championship Decks 2003

Torment

Discard a card from your hand: Switch Aquamoeba's power and toughness until end of turn.

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.

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.

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.