Development and updates on this website have come to an end. There won't be any more update in the foreseeable future.
More details here 
Come, Arsene!
Active
1 Preemptive
Joker enters the battle with his Special Skill. Selects 1 enemy to deal 200% damage to and double its Exploit Weakness stacks. Active Skill damage increases based on the number of tiles occupied by the target.
Special Skill: Deals damage to all enemies according to the number of P5R collaboration characters deployed. Deals more damage to enemies with WEAK status, and dispels all WEAK status. When all enemies have WEAK status, a Special Skill display is triggered.
Exploit Weakness: Enter WEAK status after gaining 100 stacks of Exploit Weakness.
Right there!
Chain
4913
Deals 150% damage to the 3 nearest enemies within 4 surrounding clusters, and inflicts 3 stacks of Exploit Weakness to each enemy hit.
Exploit Weakness: Enter WEAK status after gaining 100 stacks of Exploit Weakness.