Efficient Burst [Metamagic]
When converting a single-target effect to a five-foot area effect (see the Target section), spend only half the usual cost, rounded up. Increasing the area further thereafter costs the normal amount (one half primary sphere level).
For example, Lalu the mystic sorcerer has the Efficient Burst feat and wants to use a remote explosion Pyrotechnics effect on a group of enemies. He decides the effect will do 5d6 damage (Pyro 3 for a mystic sorcerer) and that he wants to encompass a 10-foot radius area 25 feet away from himself. He pays Pyro 3 for the damage and an additional Pyro 1 for the 25-foot distance. Normally, converting this Pyro 4 effect to a 5-foot radius would thus cost an additional Pyro 4, but using Efficient Burst the cost is only Pyro 2 (half the normal cost). Increasing the radius from 5 feet to 10 feet costs half of the total sphere points used in the original effect—another 2 points. Thus, the total cost of the effect is 8 (3 for damage, 1 for range, (3 + 1) / 2 = 2 for the first 5-foot burst, and (3 + 1) / 2 = 2 more to increase the burst radius to 10 feet).