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Is it possible to take both? the reason I ask is because some bows state in their rules that their effects don't work cumulatively with magic arrows however the rest make no mention either way. Since I can't find anything in the main rule books about it i'm not sure whether this means the ones that don't say they don't work actually do.
ye that's about as clear as mud but oh well.
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As far as I'm aware you can only have 1 magic effect per item but... I don't know if it means you can't take both and choose the effect or if you get for example +1 to hit for the bow and armour piercing or whatever for the arrow.
That was no help at all... Lol.
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As long as the rules for either the Bow or the Arrow don't say that you can't use them in conjunction, then yes, you may fire magical arrows from a magical bow and enjoy the effects of both.
At the end of the day, this means that any of the Wood Elf bows may fire any of the Arrows. The only time that the effects will not be cumulative, is in the case of the 'Hail of Doom Arrow' which explicitly states that the effects of magic bows are ignored for this shot.