"Educated Guess" values have been recorded from Corecraft test server which isn't a primary source (credit for that research goes to NiM and Shiro). However, when I've tried to verify some of their values now and in the past, they've come out pretty much right and in my opinion are preferable to any guessed values and can be used for the time being until primary sources are studied.
Mob
Damage
Health
Mana
Abilities
Immunities
Source
Comments
Ethereal Crypt Raider
3029-4284
27350
0
Charge for +70, Soul Strike for 220%, Battle Shout
?
WoW Bestiary
N/A
Ethereal Scavenger
3534-4998
22355
0
Singe ticking 830-884, Shield Bash for 133-161, Strike for +300
?
WoW Bestiary
N/A
Ethereal Sorcerer
798-1158
17594
73320
Slow, Arcane Missiles ticking 2057
?
WoW Bestiary
N/A
Arcane Fiend
1000-1400
2714
16155
Arcane Explosion for 1450-1650
?
Educated Guess
N/A
Pandemonius
2850-3980 (shadow)
119556
0
Dark Shell for 1500, Void Blast for 2700-3000
Immune
Educated Guess
N/A
Ethereal Priest
718-1024
19681
73320
Heal for 16000-18000, Holy Nova for 2590-3170 heal and half damage, Power Word: Shield for unknown amount
?
Melee from Bestiary, Educated Guess
N/A
Nexus Terror
2700-3700 (shadow)
49513
0
Psychic Scream, Curse of Impotence, Shadows Embrace for 2850-3150 over 6sec, Death Coil for 714
?
Educated Guess
N/A
Mana Leech
1150-2000
7406
3155
Faerie Fire, Mana Burn for 1900-2800 (half damage), Arcane Explosion for 1200-2000 upon death
?
Educated Guess
N/A
Ethereal Darkcaster
1598-2319
16086
7332
Shadow Form, Mana Burn for 2800-3200 (half damage), Shadow Word: Pain ticking 1100 (before Shadow Form boost)
Dual Wield, Gouge for 250-260, Phantom Strike ticking 940-1370
?
Educated Guess
N/A
Ethereal Spellbinder
762-1106
15498
75000
Immolate for 2700 and 787 ticks, Summon Ethereal Wraith, Counterspell
?
Melee from Bestiary, Educated Guess
N/A
Ethereal Theurgist
649-942
20225
75000
Polymorph, Strike for +400, Blast Wave for 3000-3400
?
Melee from Bestiary, Educated Guess
N/A
Ethereal Wraith
1900-2500 (my inference), 3600-4800 (CC)
6930
3309
Shadow Bolt Volley for 688-805/3000-4000 (retail Wowhead/Corecraft)
?
Damage scaled from normal difficulty values in Bestiary with same modifier as Crypt Raider. Damage taken blindly from retail Wowhead
Corecraft values didn't pass my sanity check so I tried to figure something out. However, MT has demonstrably been doable even with these extreme values and while I'm not aware of such a thing, they could have been backed by retail sources I couldn't find after a quick search
Nexus-Prince Shaffar
3400-4700
143443
33090
Blink, Frost Nova for 850-1050, Fireball for 1600-2200, Frostbolt for 1475-1925
"Educated Guess" values have been recorded from Corecraft test server which isn't a primary source (credit for that research goes to NiM and Shiro). However, when I've tried to verify some of their values now and in the past, they've come out pretty much right and in my opinion are preferable to any guessed values and can be used for the time being until primary sources are studied.