ShiroKuro

ShiroKuro is the third Raid boss of Blue Archive. The fight consists of two stages, one versus Shiro and one versus Kuro.

Shiro will toss ball bombs at your students and the placement of these balls is completely random. Any characters inside the red circles will take damage and characters inside more than one circle will take damage from both bombs so pay close attention if you want to survive.

Shiro's second attack is that he will toss a giant rolling ball straight down the lanes starting with Middle lane, Left lane and then Right lane in that order. The strategy to survive this attack is to either get out of the way using abilities that forcibly move your characters such as Izuna's EX skill to relocate her, Fuuka's EX skill that makes all your characters in range go to the designated location or Serina's med kit to relocate one student.

Another popular strategy is to block the ball using a character such as Shizuko but they need to be leveled enough so that their summon can survive and properly block the ball. Time the EX skill to land it right in front of Shiro when he's about to throw the ball and Shizuko's stall will cause the ball to disappear when both clash if you timed the EX skill correctly and the stall has enough HP to survive one hit from it.

Kuro will shoot spinning teacups at your characters. The pattern for the teacups is always the same unlike Shiro's bomb RNG so you can plan around it. The teacups will disappear after hitting something but keep in mind a character can be hit by more than one if they are in the path of more than one. Again, you can block these cups with a character that summons cover, tank the damage by making your beefier characters take the brunt of the damage or simply just keep shooting and heal anyone that gets low if your characters are strong enough.