Trinisphere and Fuse

[Water0]

I think the interaction here is that the fused card is one card and, therefore, one cost. Do I pay 3 for wear//tear fused or 6?

[A Former User]

@Water0 said:

I think the interaction here is that the fused card is one card and, therefore, one cost. Do I pay 3 for wear//tear fused or 6?

You are casting a Red White spell with converted mana cost of 3. Trinisphere doesn't care. Chalice of the Void on 1 or 2 doesn't care. And neither does Mental Misstep.