One by One is a Normal Trap Card.
Trap Cards are normally Set first and can be activated on a later turn, often in response to an action.
On the current TCG and OCG Forbidden & Limited lists tracked here, One by One is Unlimited.
YGOPRODeck lists One by One for these formats: Common Charity, TCG, OCG, Master Duel.
A listed print of One by One appears in Lightning Overdrive (LIOV-EN078) at Common rarity.
Among markets shown on this page, the lowest listed snapshot for One by One is about $0.03 on Cardmarket (prices change frequently).
