Fizzle Magic

[Scott Adams]

Does anyone handle situations like:

With the segmented combat system
MU allocates Mana for FireBall
Missile phase they kill all the bad guys..nothing is left
Magic Effect - Fireball goes where?  No enemies

Some magic it doesn't matter but has anyone done a variant to where the
magic is just wasted or does it have to go somewhere?
Since by the time you allocate, missile fire kills everyone, and magic effect
its nothing to do.

I've not seen a system handle this aside from Stormbringer which allows you
to bring back in some of the magic (mana) sorta like a regeneration of the
mana you don't use.

Ideas?