So how would a fireball made of Essential Fire work? Well, the basic rule is that essential stuff is three times as awesome as normal stuff. You
could triple damage, but at some point that hits diminishing return. So I suggest:
Essential Fireball
Missile
Throw a ball of essential fire from one hand. This has ½D 25, Max 50, Acc 1. When it strikes something, it vanishes in a puff of flame. This spell is likely to ignite flammable targets.
Cost: Any amount up three times your Magery level per second, for three seconds. The fireball does 1d (3) burning damage per three energy points.
Time to cast: 1 to 3 seconds.
Prerequisites. Magery 2, Create Fire, Shape Fire, and Essential Fire.