If you active other cards to increase ATK, place this card as the last link in the chain. When you do, the other ATK changes occur after your monster's original ATK is doubled. If you do not, after you boost your monster's ATK, this card will ignore the changes and make the ATK of your monster becomes double its original ATK.
This card's effect will change the affected monster's ATK to double its original ATK, whether or not there are other effects being applied to the card in question at the time. If a continuous card effect is in play, such as the ATK boost from "Fire Formation - Tenki", or the reduction of "Burden of the Mighty", those effects will not be applied to the affected monster until after Damage Calculation is resolved. If the effect was not a continuous effect, its effect will be negated by this card's effect.
Like Honest and "Bujingi Sinyou", using this card will reset the ATK of the monster affected, if it had previously been lowered.
Use this to your advantage to negate the downside of summoning a monster while "Black Garden" is in play. After Damage Calculation is complete, the affected card's halved ATK will be returned to normal.