Forum:Stat modifiers/Knowledge

I understand that if you flip a face up monster facedown or if that card leaves the field, effects that were affecting it will reset (such as stat modifiers). However, can you use stat modifiers on facedown cards? For example, Performapal Sword Fish reduces the ATK and DEF of all monsters the opponent controls by 600. This effect is permanent, even if Sword Fish leaves the field, right? However, what if some monsters the opponent controlled were in facedown defense mode when Sword Fish was activated and was later flipped face up? Would the monster still have it's original stats? Also, what if a card with 2100 or less ATK was switched facedown, and the other player summoned Number 50: Blackship of Corn? Could you target the facedown monster even though the monster's stats are technically unknown (this was mentioned on the common ruling FAQ page)? Also, on a side note, if there is a card protecting another card from destruction, and the opponent attempts to destroy them both at the same time, does the card being protected survive because at the time, the other card was protecting it?Surya97 (talk • contribs) 03:01, August 23, 2016 (UTC)