Boundless Necromancer

A brief description of the manhwa Boundless Necromancer:
[By the studio that brought you and !]
I never thought I could become a hunter.
I never thought I’d get the chance.
But that wasn’t the case.
「 The ‘Tower of Trials’ has selected all suitable candidates from Earth. 」
「 Please select your DIFFICULTY. 」
「 The Rewards you get will be directly proportional to your chosen DIFFICULTY. 」
I was given a chance just now.
A special one, at that.