Telegraphed Attacks/Abilities?

[Spellbound]

So I have this ability that lobs explosive balls of energy. How do I make it so that 1 second before the missile launches, an aoe that everyone can see will appear, indicating to all players that this is where the ability will hit. The aoe effect only disappears after the missile has impacted or if the ability is canceled before it fires.

 

[Dr Super Good]

Check out Archangle from HotS (both Swam and Storm), it used the system to warn you of missiles and other nasty abilities.

The idea is to create a targeting marker on the ground on launch/channel that is destroyed on impact/fail. By default everyone should see it.