Area Effect

[smugg]

Does the default use of Area Effect attacks include altitude (or depth) charges?

I've found in the rules that an attacker can target a hex or another character's DCV. Does there need to be a solid present for a hex to be targeted? Let's say Defender is being fired upon by Mechanon who is using his Explosive Projectiles. Early in the fight, Defender is on the ground and obviously Mechanon can target the hex in which Defender stands. Later in the fight, Defender is flying at some point over Mechanon's head. If there is nothing close by to Defender upon which an Explosive Projectile can be exploded, can Mechanon 'set' his Explosive Projectile to go off near Defender (like in his hex)?

If a power advantage needs to be purchased for this effect, what should it add to the cost of the already steep AE advantage?

[Steve Long]

Targeted hexes can be on the ground, in the air, underwater, whatever. The important thing is having LOS and range to them, not their "location" (unless some Limitation indicates otherwise).