Arknights: Guide to CB-EX5 Challenge Mode

This guide will step through a strategy for clearing CB-EX5 Challenge Mode.  If you are looking for Normal mode or the Event Mission, or for other Event information or Operation clear guides, see the following:

Challenge Condition: Caster Operators cost 3x more to Deploy

• The main challenge for this map is how to place blockades so that the Desperate Fanatics don't path next to a Command Terminal and destroy it.  We will present block placements below.
• Another challenge is the Bulldozer at the end of the stage, which requires block 3, and comes at the same time as a lot of other enemies.  We will handle him with slowing and kiting until he can be blocked.
• Most enemies are low RES and high DEF, outside of the Casters, so Arts Damage Operators will be more effective.  Since our Caster Deployment Cost is increased, we must rely on Supporters or other non-Casters that can provide Arts damage
• The Fanatics will quickly kill any Ranged Operators, so we must be careful with our Deployment to make sure they are not targeted.

• 1 Skill-DP-Recovery Vanguard, V1
• 3 Supporters, Su1-Su3.
• 1 ST Medic, M1
• 1 Control Specialist, Sp1
• 3 Melee operators, ML1 - ML3 that we will use to help with blocking, protecting our ranged Operators, and adding DPS.  Arts Guards like Astesia or Mousse are excellent.  So are Operators with high survivability, Arts Damage, or Crowd Control.  Examples include: Indra, Hellagur, FEater, Specter, etc.
• 1 Defender, D1
• Flex - Best options for Flex are melee Operators to replace any that die, or a strong ST Caster that can be possibly be deployed for the last wave.

Here is an example of the team I used:

Unit placement can be seen in the image below, and deployment order should be done exactly as presented.  Each Operator can be placed as soon as there is sufficient DP.

Deployment Order: 

1. V1: Siege - Skill-DP-Recovery Vanguard
2. Su1: Angelina - Slower Supporter
3. Su2: Glaucus - Slower Supporter
4. First block at H6
5. M1: Shining - ST Medic 
6. ML1: FEater - Pusher Operator (high Physical Dodge and Push gives her good survivability)

At this point we are at our Deploy Limit, and the first wave is passing through our center.  It should look something like this, with the first major enemy wave path shown with the red line:

Before we can deploy any more Operators, we need to activate our Command Centers.  After the first wave has been defeated:

• Place a block at E9
• Remove the block at H6
• Place a block at B6
• Activate one of the Command Centers
• Deploy Me2: Indra - Brawler Guard

Wave 2 will path like this:

As we are able, we will activate the next Command Center, and the Deploy Sp1: Manticore - Control Specialist:

As the 3rd wave emerges from the bottom right C11 we:

• Remove Block B6
• Place a Block at H6
• Place a Block at D2
• Activate the last Command Center
• Deploy Me3: Specter - AoE Guard
• Retreat V1 and place D1 (this can happen earlier at any time if necessary, but it is good to keep our DP generator out as long as we need DP)
• when the last enemies of wave 2 are dead, retreat Me2 and place Su3 (or a flex Caster if we have enough DP.

The last Wave comes at us from both sides.  It will look like this:

The last thing we have to do is buy our team enough time to take out the Bulldozer.  To do this we will do some block juggling.  After the Dozer has passed through the center, remove block H6.  Before he gets to F2, place a Block on it, and he will turn around and pass again through our center.  

After he passes the center, remove block F2, and place one on H6 before he gets there (If you need more time, you can probably also remove E9 and place a block on F6 to give him a longer kiting route).  Repeat the process until your Defender is able to block him.

Enjoy the OP!