Arknights 4-7 is a main story boss battle found in Episode 4. The key to this stage is managing the Infused Originium Slugs (exploding spiders).

The Setup

Recommended Operator Elite 1 Lv. 50

An Operator that can silence (eg. Lappland) is particularly helpful as can stop Oroginum Slugs from exploding. However this example will show how the stage can also be cleared without.

Here are the operators used in this example:

  • 2x Sniper (ST)
  • 1x Sniper (AoE)
  • 2x Vanguard
  • 1x Guard
  • 1x Caster (AoE)
  • 2x Healer
  • 2x Defender
  • Shaw (with Rank 4 Skill)

Phase One

  1. Sniper (ST) in position (A) facing up. This will kill the two Slugs in position (X).
  2. After the two Slugs are killed deploy your Vanguard in position (B) facing right.
  3. Once you have enough deployment points place your Guard in position (C) facing right.
  4. Vanguard in position (X) facing up. This will kill another two Slugs. Return your Vanguard after the second slug is killed but before it explodes.

Phase Two

  1. Sniper (ST) in position (D) facing right.
  2. Healer in position (E) facing up.
  3. Shaw in position (F) facing right. This will push the two slugs to the left and kill them. Return Shaw after she has pushed the Slugs. Your Vanguard will take a bit of damage but will survive.

Phase Three

  1. Healer in position (G) facing down.
  2. Caster (AoE) in position (H) facing up. After the 4 Slugs on the left are killed you can return your Caster (AoE).

Phase Four

  1. Replace your operators in position (B) and (C) with your Defenders facing right. Your stronger Defender should take position (B).
  2. Sniper (AoE) in position (H) facing right.

At around 41 Kills, after the Monster Mk II (highlighted in green above) has passed position (I), deploy your Vanguard in position (I) facing up to kill the last 2 Slugs. Return your Vanguard after the second slug is killed but before it explodes.

Phase Five (Optional)

This part is optional. At around 48 Kills you can deploy your Guard in position (J) facing right to protect your Sniper (ST) from the Caster Leader (highlighted in green).

If you are struggling with the final wave you can also deploy your Vanguard in front of your Defender in position (C).