BrownDust-ism.

Addicted To Gacha

Campaign 41-3

Requires 9 horseshoes, and you can fill and level other 7 spots for ★1 mercs.  It gives 2152 exp points.  From what I hear, if you use exp booster you run once and you can max level them.

  1. ★6 Octavia+9
  2. ★5 Maya+9