Regretful Rebirth 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, Regretful Rebirth is Unlimited.
YGOPRODeck lists Regretful Rebirth for these formats: Duel Links, Common Charity, Edison, TCG, OCG, Master Duel.
A listed print of Regretful Rebirth appears in Onslaught of the Fire Kings Structure Deck (SDOK-EN037) at Common rarity.
Among markets shown on this page, the lowest listed snapshot for Regretful Rebirth is about $0.20 on TCGPlayer (prices change frequently).
