This mob's AE is pretty brutal at times, and doesn't match the spell effect listed. Below is extract from my logs, as you can see at time he double hit for ~150k each, insta-killing group members/mercs alike. Other times it hit for far less.
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse begins to cast a spell. <Wirlwind Strikes>
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches Brokkah`s pet for 37837 points of damage.
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches an armored spellweaver for 12481 points of damage.
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches Geaggo for 10630 points of damage.
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches Giaty for 111304 points of damage.
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse says 'This is the -pocalypse!'
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches Giaty for 111304 points of damage.
[Tue Nov 22 19:47:51 2016] Giaty has been slain by Reese the Rhinopocalypse!
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches Euphos for 150544 points of damage.
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse says 'This is the -pocalypse!'
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches Euphos for 150544 points of damage.
[Tue Nov 22 19:47:51 2016] Euphos has been slain by Reese the Rhinopocalypse!
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches Brokkah for 54802 points of damage.
[Tue Nov 22 19:47:51 2016] Reese the Rhinopocalypse punches YOU for 32150 points of damage.
[Tue Nov 22 19:48:16 2016] Reese the Rhinopocalypse begins to cast a spell. <Wirlwind Strikes>
[Tue Nov 22 19:48:16 2016] Reese the Rhinopocalypse punches an armored spellweaver for 34054 points of damage.
[Tue Nov 22 19:48:16 2016] Reese the Rhinopocalypse punches Geaggo for 82540 points of damage.
[Tue Nov 22 19:48:16 2016] Reese the Rhinopocalypse punches Brokkah for 6982 points of damage.
[Tue Nov 22 19:48:16 2016] Reese the Rhinopocalypse punches YOU for 147206 points of damage.
[Tue Nov 22 19:48:16 2016] Reese the Rhinopocalypse says 'This is the -pocalypse!'
[Tue Nov 22 19:48:16 2016] Reese the Rhinopocalypse punches YOU for 147206 points of damage.
[Tue Nov 22 19:48:16 2016] You have been slain by Reese the Rhinopocalypse!
[Tue Nov 22 19:48:41 2016] Reese the Rhinopocalypse begins to cast a spell. <Wirlwind Strikes>
[Tue Nov 22 19:48:41 2016] Reese the Rhinopocalypse punches Geaggo for 10630 points of damage.
[Tue Nov 22 19:48:41 2016] Reese the Rhinopocalypse punches Brokkah for 31533 points of damage.
[Tue Nov 22 19:49:06 2016] Reese the Rhinopocalypse begins to cast a spell. <Wirlwind Strikes>
[Tue Nov 22 19:49:06 2016] Reese the Rhinopocalypse punches Brokkah`s pet for 165677 points of damage.
[Tue Nov 22 19:49:06 2016] Reese the Rhinopocalypse says 'This is the -pocalypse!'
[Tue Nov 22 19:49:06 2016] Reese the Rhinopocalypse punches Brokkah`s pet for 165677 points of damage.
[Tue Nov 22 19:49:06 2016] Brokkah`s pet has been slain by Reese the Rhinopocalypse!
[Tue Nov 22 19:49:06 2016] Reese the Rhinopocalypse punches Geaggo for 60967 points of damage.
[Tue Nov 22 19:49:06 2016] Reese the Rhinopocalypse punches Brokkah for 30260 points of damage.
[Tue Nov 22 19:49:31 2016] Reese the Rhinopocalypse begins to cast a spell. <Wirlwind Strikes>
[Tue Nov 22 19:49:31 2016] Reese the Rhinopocalypse punches Geaggo for 96922 points of damage.
[Tue Nov 22 19:49:31 2016] Reese the Rhinopocalypse punches Brokkah for 10714 points of damage.
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[Tue Nov 22 19:51:36 2016] Reese the Rhinopocalypse begins to cast a spell. <Wirlwind Strikes>
[Tue Nov 22 19:51:36 2016] Reese the Rhinopocalypse punches Geaggo for 162390 points of damage.
[Tue Nov 22 19:51:36 2016] Reese the Rhinopocalypse says 'This is the -pocalypse!'
[Tue Nov 22 19:51:36 2016] Reese the Rhinopocalypse punches Geaggo for 162390 points of damage.
[Tue Nov 22 19:51:36 2016] Geaggo has been slain by Reese the Rhinopocalypse!
[Tue Nov 22 19:51:36 2016] Reese the Rhinopocalypse has been slain by Brokkah!