This Modified Version of the Flame Crystal Staff that use Mana instead of Essence of Fire. Its power also have been increased but for an increase in material cost. Here is the details (Vanilla to Modded):

Primary Attack: Fireball

1 charge: entity damage from 10 to 15, entity damage radius 2 (unchanged), Damage falloff from 0 to 0.4, use 12.5 Mana.
2 charges: entity damage from 20 to 30, entity damage radius from 3 to 4 , Damage falloff from 0 to 0.4, use 25 Mana.
3 charges: entity damage from 30 to 50, entity damage radius from 4 to 6 , Damage falloff from 0 to 0.4, use 37.5 Mana.
4 charges: entity damage from 40 to 80, entity damage radius from 5 to 8 , Damage falloff from 0 to 0.4, use 50 Mana.

Secondary Attack: Flamethrower
Cost 10 Mana/s.
Increased Base Damage from 12 to 24
Extended Range by almost 3 time (from 5.5 to 16).
Apply Burn on Mobs and Terrain

Ability One: Fire Trap
Start Radius from 1 to 2
End Radius from 5 to 8
Height from 2 to 4
Apply Mana Burn which is not doused by Water

Passive (While holding the Staff):
Grants +100 Mana (used mostly if you don't have mods that provide Mana)
Grants Burn and Mana Burn Resistance (No Lava Burn Resistance)

Material Cost of Crafting:
Ruby: 1 (unchanged)
Silver Ingot: from 8 to 32
Gold Ingot: from 8 to 24
Essence of Fire: from 20 to 100

I mostly did this staff to have fun for myself, but I thought may as well posting it if peoples were interested into a Flame Crystal Staff using Mana instead. If you wanna do some modification because Damage or Range, or anything are too high, feel free to do so.

Kagami's Mana Flame Crystal Staff