This card's effect that doubles damage inflicted to your opponent by the effects of "Trickstar" Link Monsters linked to it is a Continuous Effect.[1]
This card's effect that increases its ATK is a Trigger Effect. (It does not target, and will also activate during the Damage Step.)[1]
This card's effect that changes its ATK gain to 0 and adds a "Trickstar" monster from your Graveyard to your hand is a Trigger Effect that activates on the field. (It does not target.)[1]
Changing the ATK this card gains from its effect to 0 and adding a "Trickstar" monster from your Graveyard to your hand do not happen simultaneously.[1]
You must always apply the part of the effect that changes the ATK this card gains to 0, but you can choose not to apply the part of the effect that adds a "Trickstar" monster from your Graveyard to your hand.[1]
Q&A Rulings
Q: If my opponent activates the effect of "Trickstar Band Sweet Guitar" that changes its ATK gain to 0 and adds a "Trickstar" monster from the Graveyard to their hand, can I chain the effect of "Ghost Belle & Haunted Mansion"?
A: If the effect of "Skill Drain" is applied after "Trickstar Band Sweet Guitar" gains ATK by its own effect, the effect stops applying and it no longer gains ATK. Even so, if "Trickstar Band Sweet Guitar" attacked, its effect will activate during the End Phase. Even if the effect of "Skill Drain" is no longer applying at that point, you cannot apply the part of the effect that changes the ATK increase to 0, so you cannot add a "Trickstar" monster from your Graveyard to your hand.[3]