I pulled 2 Innes' one with +Spd/-Atk and the other was neutral. I'm not sure which one I should use. I was hoping to use a brave bow build on him but not sure if the -atk would ruin it. Any advice would be much appreciated.
I honestly think it's pointless to just slap brave bow on every archer. Innes has an interesting and unique bow combined with super high resistance making him one of the best anti mages. Considering you want to brave bow him makes me believe that you already have a brave bow user, so why not use them both for different situations? Also if you really want brave bow, then it's only worth it on +atk.
There is no point in having build diversity. In Arena and Arena Assault, you want as many overpowered units as possible. Brave Bow is simply superior.
If you want to aim for the top, you need as many Brave Bow archers and Blade mages as possible. Having build diversity is counter productive if it does not help you achieve that goal.
Neutral Innes can be good with a brave bow, however he also has a great kit with Nidhogg. I've got a -Atk +Def Innes and he is an amazing magic tank. With fury, he can can even tank Reinhardt with full cav buffs and some merges, provided he is surrounded by some allies. If you don't have a counter to Reinhardt and blue mages, he is your man.
If you have the resources to afford a Brave Bow build, I would go for the neutral nature.
If you go with Nidhogg, you need two allies by his side at all times for it to out perform Brave Bow. That severely limits the rest of your team's potential so I would not recommend it.
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