Damage from unit's staff will be calculated the same as other weapons.
Wrathful Staff 3
Skillsets that use skill
Scattered Cherry Blossoms (Offensive Support)
Fiery Festivities (Offensive Support)
Mother of the Dark (Offensive Utility)
Witch’s WAHnd (Offensive Support)
Yied Traveler (Offensive Support)
A Sister’s Admiration (Offensive Support)
Hel Bringer (Offensive/Utility)
Bleating and Babbling
Shining Time (Offensive Support)
Jealous Streak (Offensive Support)
Raymond's Confidant (Offensive Utility)
Dazzling Princess (Team Crippler)
Prepare to Be Dazzled! (Offensive Support)
Hanami in Full Bloom (Chip Damage)
Not Delicate (Team Crippler)
Just like Minerva! (Offensive Healer)
A long-awaited skill for lovers of clerics, Wrathful Staff enables them to take on offensive roles. Normally, combat damage inflicted from staves is halved, but with Wrathful Staff, the damage is applied normally. While clerics typically do not have the stat lines or weapons to deal significant damage, Wrathful Staff allows them to deal reasonable damage. By providing meaningful damage alongside healing, they can support the team in more ways than just one.
Wrathful Staff is only available on clerics, and assumes that the unit is building towards an offensive capability as opposed to a supportive one where possible. High attack and speed, as well as a decent resistance, allow for more damage and the potential for a double attack. Weapon choice varies depending on the Cleric's secondary role. Candlelight and Fear are decent choices to debuff enemies for an easier kill. Gravity in conjunction with Dazzling refinement lets your Cleric attack the enemy and retreat away for consistent chip damage.
Clerics have limited A slot skill choices, with Atk+3 or Spd+3 being relatively cheap and accessible. In general, offensive stat booster that is not Fire Boost should work well. The C slot depends largely on playstyle, but the recommended options are Breath of Life (+ the Breath of Life seal), Savage Blow or the traditional Hone or Fortify skill.
Once again, the Dazzling Staff refinement is an almost mandatory partner, as it allows your cleric to attack without risk of counterattack.
Clerics themselves are not common units, due to their low stats and healing being less useful due to short match times. Regular mages deal normal damage without costing a skill slot, and on average have much better stat spreads for inflicting damage. However, the skill itself does not have any inherent weaknesses. Opposing clerics with Wrathful Staff can deal surprising damage, but often have very low defense stats, making them easy to KO with most physical damage dealers.
Without Dazzling Staff, however, your Cleric may meet a swift end if confronting a unit that can fight back.