How to build magic bow?

[Matti]

Trying to clear Darkness 15 with magic bow, but can't find a build with enough single target DPS to clear out higher HP baddies. tried pure gun, summon and elemental, but always falls short. any tips?

[Gem of Temporarity]

Move to maximize reload damage. Not getting direct impact sometimes results in more reload damage later.

Gun builds benefit from non-splinter projectile production as stuck arrows do full reload damage even if they impacted for a tiny fraction of bullet damage. Fan fire makes many more with mini clip.

Bomb caller evolution wants bullet size but not speed. It is the one with the highest potential bullet damage against a single target(1x impact + 3x explosion), but may struggle to hit mobile enemies with explosions without freeze.
Arrow caller doesn't use up it's pierce making it somewhat effective at using on-hit stuff including flat damage which it still deals on impact. Maximize bullet speed for this one

[Nanashi]

Bullet Damage, Fire Rate, Reload Rate
Combine that with as many + bullets you can get (this is like the one weapon with which shooting ten projectiles around isn't entirely ♥♥♥♥).

Get anything that helps you survive if you cannot get any of those other stats in a level up. Stuff like Movement Speed, Freeze, Curse (for 30% damage on cursed targets if you get the second upgrade), soul hearts, holy shield, etc.

The Magic Bow evolutions are all kind of nice but I went with the electro version because I like the pull-back on arrows and the other two removed that aspect.

Just cleared 15 with Yuki and Bow on first try with that general strategy.

And aside of that any decently lucky summoner build should work as always regardless of what you do with the weapon.

It's much more about just staying alive then actually killing stuff. The AoE with that kind of build should be enough if you circle around bosses a bit.