I like special arrows too, but I see one main flaw in having a myriad of them available to the player... where did they come from? I feel that each settlement of fir'Bolg should have a different type of special arrow. So for example (from Chimera) the fir'Bolg of Ruewood have fever arrows and the Bowmen from Muirthemne use fire arrows.
Other things like the bow of stoning and the lightning bow are too strong for special arrows so I feel they should be only for the heroes. Very similar to how ne'Ric the fir'Bolg hero of Ruewood had his storm strike arrow. Especially since a stoning arrow takes a Journeyman to fix, whereas a fever arrow is only temporary.
Let me know what you think about this.
Sincerely,
Pimpy™
