Here is the full list of all 12 Tartarus Longo Itinere achievements.
Killed 50 bosses
Killed 100 bosses
Killed 50 monsters
Killed 100 monsters
Killed 200 monsters
You lost 10 times
You lost 50 times
You lost 100 times
The Plague's Alchemist join the Longo Itinere
The might Gabriel join the Longo itinere
The Leader of Sin Nombre join the Longo Itinere
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