Forgetting: What Monsters Lose When They Stop Being Face-Up

When a monster stops being face-up — by being flipped face-down, or by

being temporarily banished (banished by an effect that will return it) — it

"forgets" certain information about itself. When it comes back face-up it is, for

many purposes, treated as a fresh monster. But it does not forget everything,

and face-down vs. temporarily banished differ: a temporarily banished monster

retains more than a face-down one.

This is the same family as

Lingering Effects from Summon Material

and ATK Effects: Past Summon Facts vs. Current Game State.

Forgotten by BOTH (face-down and temporary banish)

• Stat modifications — lingering ATK/DEF changes fall off.
• Previously applied lingering effects — boosts and protections it had gained

(e.g. a Yang Zing material boost) are gone.

• Properties of the cards used to Summon it — their Names, Attributes, Types,

Levels, and the number of materials. Conditions that checked the materials'

properties are lost.

• Whether a "once per turn" effect was already used this turn — it becomes

usable again. Exception: an effect that flips the monster itself face-down

is still remembered.

Remembered by BOTH

• Which specific cards were its materials — the material identities

(Fusion / Synchro / Xyz / Link Materials). So De-Synchro still works on a

previously flipped/banished Synchro Monster: the materials' identity survives

even though their properties are forgotten.

• **That it was Set / Normal / Tribute / Special Summoned, including the type of

Special Summon** — e.g. Obelisk the Tormentor still knows it was Special

Summoned, and March of the Monarchs still recognizes a Tribute-Summoned

monster.

• The turn it was Set / Normal / Tribute / Special Summoned — so it still

counts as "Summoned this turn." Per reference sheet 2 ("the turn that monster

was ... Summoned"), this is retained by both face-down and temporary banish.

Differs: face-down vs. temporary banish

• Where it was Summoned from: face-down forgets (loses its Extra-Deck

origin, so Shaddoll Fusion's "if you control a monster Special Summoned from

the Extra Deck" no longer sees it); temporary banish remembers.

• The specific method/effect that Summoned it: face-down forgets;

temporary banish partly retains it (adjusts).

• Battle Position changed this turn: face-down remembers; temporary banish

forgets.

• Declared an attack this turn: face-down remembers; temporary banish

forgets.

• Pendulum Summoned: face-down forgets; temporary banish remembers.

Summon-type exceptions (forgotten by BOTH)

• A Gemini monster that was Normal Summoned again — forgotten by both.
• That it was Flip Summoned — forgotten by both.

Judge calls

• Separate "properties of the materials" (forgotten) from **"identity of the

materials"** (remembered).

• Don't claim a flipped/returned monster keeps a lingering ATK boost or

protection it had gained — those are gone.

• It DOES still know it was Set/Normal/Tribute/Special Summoned (the fact, e.g.

Obelisk/March checks), including the turn it was Summoned — so "Summoned

this turn" survives both a face-down flip and a temporary banish. (Don't

confuse this with where it was Summoned from, which face-down does lose.)

• For Extra-Deck origin, attack/position-changed-this-turn, method-of-summon, and

Pendulum questions, ask face-down or temporarily banished? — the answer

differs.

Reference cheat sheets

The first sheet also covers returning to the deck, being sent to the GY, and

being used as Xyz Material; this ruling focuses on the face-down and

temporarily-banished columns.

Sources

YGOrganization "Demystifying Rulings, Part 13: Advanced Rulings" (ygorganization.com/learnrulingspart13). Reconciled with the two community cheat sheets shown above.

• db.ygoresources.com Q&A 12487 (Konami-flagged "Important Precedent"): a hard "once per turn" effect resets and can be used again the same turn if the card leaves and returns to the field, including being flipped face-down then face-up or temporarily banished and returned — and you may reselect the same option. Confirms "whether a 'once per turn' effect was already used this turn" is forgotten when the card stops being face-up / leaves the field. https://db.ygoresources.com/data/qa/12487
• db.ygoresources.com Q&A 213 & 69 (Konami-flagged "Important Precedent"): the broad fact that a monster "was Special Summoned" / "was Ritual Summoned" persists through a face-down flip (e.g. Special Hurricane still destroys a face-down monster that was Special Summoned) — only the narrower "summoned from where / using which named cards" facts are forgotten by face-down. Confirms the "remembered by both" rows above. https://db.ygoresources.com/data/qa/213 · https://db.ygoresources.com/data/qa/69