I am playing a Warlock with the Eldritch Strike power, which has the following piece of text: This power counts as a melee basic attack.
This means that I have two MBAs, my normal strength-scaling MBA, and the Con-based Eldritch Strike.
It's pretty clear that as the character's player, I can choose which MBA I use at any given moment.
My question is when my character is subject to a power that forces me to make an MBA, such as the Vizier Devil:
Word Of Command: Choose one creature within 2 squares of the devil. The devil slides that creature 3 squares, and the creature makes a melee basic attack as a free action against a creature of the devil's choice.
It's clear that the devil is telling me who to attack, but not which attack my character uses or who would get to decide.
So, who makes the decision?