Mortal Arena runs from difficulty 1 to 1, and everything in it drops at item level 120 no matter how deep you go. It opens at character level 100 once you have cleared Nightmare 10, and you go in alone or with a party you brought.
Wipe here and you lose nothing.
33 bases and 22 Uniques drop here, and 7 bosses belong to it: Imp Overlord, Frost Wyrm, Cinder Wyrm, The Spider King, Thunderroc, The Mountain Sire and The Dawn Matron.
Modes
1 mode
| Mode | Goes up to | iLvl | Loot × | XP × | Getting in | Renown | |
|---|---|---|---|---|---|---|---|
 | Mortal Arena no matchmaking · effective threat 44+2/step |
1 | 120 | ×1.6 | ×0 | Lv 100 Nightmare 10 |
300 + 0/step |
Bosses
7 bosses
| Boss | Biome | HP | Uniques here | |
|---|---|---|---|---|
 | Imp Overlord | Demon Gate | 960 | 1 |
 | Frost Wyrm | Frostmere Reach | 1050 | 2 |
 | Cinder Wyrm | Cinder Forge | 900 | 3 |
 | The Spider King | The Sporeveil | 1140 | 1 |
 | Thunderroc | Skyreach Bastion | 930 | 5 |
 | The Mountain Sire | Cragmaw Deep | 1350 | 2 |
 | The Dawn Matron | Dawnspire Sanctum | 1020 | 8 |
Uniques you can find here
Tithe of the Court
Immaculate Mortalcoil Band · Imp Overlord
Bellows-Stride
Exalted Warpath Boots · Cinder Wyrm
The Furnace Psalter
Exalted Epitaph Tome · Cinder Wyrm
The Ember Ledger
Immaculate Ransom Band · Cinder Wyrm
Solstice Vigil
Immaculate Wintersend Band · Frost Wyrm
The Long Slide
Exalted Stargrazer Boots · Frost Wyrm
The Spider King's Brood
Perfect Firstseed Staff · The Spider King
Downdraft
Exalted Stargrazer Boots · Thunderroc
Static Cling
Immaculate Stormheart Band · Thunderroc
Fulgurite
Sovereign Cometshard Dagger · Thunderroc
The Stoop
Exalted Warpath Boots · Thunderroc
Talonhook
Sovereign Veinseeker Dagger · Thunderroc
Bedrock Testament
Sovereign Anchor Tower Shield · The Mountain Sire
The Mountain Sire's Spine
Sovereign Atlas Zweihander · The Mountain Sire
The Second Verse Circlet
Sovereign Saint's Helm · The Dawn Matron
The Dawn Offertory
Immaculate Suncrown Band · The Dawn Matron
The Dawn Matron's Vestment
Exalted Aegisheart Mail · The Dawn Matron
The Usher's Aegis
Sovereign Dawnsworn Shield · The Dawn Matron
Doxology
Perfect Goldenchord Staff · The Dawn Matron
Matins
Perfect Lastdawn Staff · The Dawn Matron
The Evensong
Eternal Ancestor Relic · The Dawn Matron
The Noonday Crown
Eternal Godspark Relic · The Dawn Matron
Getting in, and what it costs to fail
before you walk in
Opens at level100
Opens at Threat1
Nightmare cleared10
Gold lost on a wipenone
XP lost on a wipenone
XP you keep from the runnone
Renown lost on a wipenone
Costs you the characterno