Guide
How the kit works
Use Defensive Assist: Risk Allocation when the active character is about to be hit. It parries the attack and deals Daze. You can then use Assist Follow-Up: Don't Break Contract for a Fire strike. Ben is invulnerable during both actions.
With enough Energy, use EX Special Attack: Cashflow Counter (Special) to block and strike with Fire DMG. A successful block strengthens the strike and triggers a Block Counter. Press again after activation for the powerful follow-up: Core Passive: Guardian gives every squad member a Shield equal to 30% of Ben's DEF +550 for 30 seconds. You can use the follow-up without first blocking an attack.
Hold the special to stay in the blocking stance. Its personal Shield weakens over time, disappears when Ben leaves the stance and then recovers. It cannot exceed 16% of his Max HP; activating the EX restores it to its maximum. Ben is invulnerable when activating Block and during the EX strikes. Without enough Energy, Special Attack: Fiscal Fist also blocks and counters, but deals Physical DMG.
Basic Attack: Debt Reconciliation has up to three Physical strikes. Dodge: Missing Invoice gives invulnerability, and Dodge Counter: Accounts Settled deals Fire DMG after a Perfect Dodge. Chain Attack: Signed and Sealed and Ultimate: Complete Payback hit a large area with Fire DMG; the Ultimate also recovers 3 Assist Points.
Build and why
Start with four pieces of Swing Jazz and two pieces of Proto Punk. Swing Jazz gives 20% Energy Regen from two pieces; its four-piece effect gives the squad 15% more DMG for 12 seconds after Ben uses a Chain Attack or Ultimate. Proto Punk adds 15% to Shield effect.
For another team-focused setup, use four pieces of Proto Punk with two of Swing Jazz. A Defensive Assist or Evasive Assist by any squad member then increases squad DMG by 15% for 10 seconds. The game's build also offers four-piece Soul Rock or Bunny in Wonderland with two-piece Proto Punk or Swing Jazz. Soul Rock gives DEF and reduces damage taken briefly after Ben loses HP to an attack. Bunny in Wonderland can increase squad DMG when Ben uses an EX or the squad uses an assist.
Choose Percent DEF as the main stat on discs 4, 5 and 6. Look for Percent DEF first and Percent ATK second in substats. Guardian's squad Shield scales with DEF, while Ben gains ATK equal to 80% of his initial DEF.
Spring Embrace is the first weapon to consider: after Ben is attacked, it raises his Energy Generation Rate, and passing him off-field transfers the buff to the incoming character. Tusks of Fury increases the Shield he provides and can raise squad DMG and Daze after an Interrupt or Perfect Dodge. Big Cylinder is another option: after Ben is attacked, his next attack to hit critically deals additional damage based on his DEF.
Leveling priority
The game's order is Core Passive: Guardian first, then Special Attack: Fiscal Fist, Basic Attack: Debt Reconciliation, Chain Attack: Signed and Sealed, Quick Assist: Joint Account, and Dodge: Missing Invoice. Start with the passive for the squad Shield, then the special category for the move you use to block and counter.
For maximum ascension, you need 800,000 Denny, 4 Basic Defense Certification Seal, 32 Advanced Defense Certification Seal and 30 Defender Certification Seal.
For all skills to the maximum, you need a further 2,905,000 Denny, 25 Basic Burn Chip, 75 Advanced Burn Chip, 250 Specialized Burn Chip, 5 Hamster Cage Pass, 9 Living Drive and 60 Higher Dimensional Data: Steel Malice.
Mindscapes worth it
For a team-focused Ben, I'd consider Reacting Force first. Successfully blocking with his Special or EX Special reduces the blocked enemy's DMG by 30% for 15 seconds. It helps the squad, but you still have to land the block.
Offense Through Defense is a good next pick for damage. A successful Block Counter with either special deals additional DMG equal to 300% of Ben's DEF. Wild Spirit is worth considering if Ben stays on field to attack: after an EX attack or follow-up, it increases Daze from his Basic Attacks, Dash Attack and Dodge Counter by 20% for 12 seconds.
You can leave Agile Adaptation for later if you mainly want protection. It increases the next counter's DMG by 30% when Ben blocks enemy damage with the invulnerability effect during either special. Careful Accounting and Meticulous Detail add skill levels rather than changing the squad Shield.
Common mistakes
Don't confuse Ben's blocking Shield with his squad Shield. Holding the block gives him a personal Shield that weakens over time. The squad Shield comes from the powerful EX follow-up, so remember the second press.
Don't hold the blocking stance indefinitely while waiting for a hit: the personal Shield gets weaker as time passes. Watch the incoming attack and use the block's activation invulnerability.
Don't forget the same Attribute or Faction condition when building a team. Without it, the squad Shield still comes from the EX follow-up, but the Additional Ability's CRIT Rate increase is not active. Also check when your set's damage effect triggers: Swing Jazz needs Ben's Chain Attack or Ultimate, while Proto Punk needs a Defensive Assist or Evasive Assist.