REDU format ruling
Slip of Fortune

Nearest-era rulings (Tengu, Sept 2011) — no REDU-specific archive exists.
Card effect (current official text)Activate only when your opponent's monster declares an attack targeting a monster. Negate the attack and remove from play the attack target monster until the next Standby Phase.
Rulings
- If the monster being attacked is removed from the field by an effect Chained to "Slip of Fortune" the attack will still be negated.
- If the monster being attacked is in face-down Defense Position, "Slip of Fortune" will remove it from play face-down and return it to play in face-down Defense Position.
- Returning the removed monster to play is not a Special Summon. "Slip of Fortune" targets 2 monsters: the attacking monster and the attack target monster.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the REDU forum — sourced change requests get reviewed.