Now who are these five?
Come, come, all children who love fairy tales.
The crux of this question is: for threshold requirement activations, when is the threshold checked? Is it 1) right before the activation of the ability, or 2) at the beginning of the phase in which the ability would be activated?
However, do note that mandatory abilities must happen first, optiona happens after. So you can't use an optional ability to change something, and THEN let that trigger a mandatory ability.