The invitation promised a chance to turn his life around.

It was a trap.

Seo Jin-hyeok enters Tower #2661 expecting an easy climb—
only to discover one cruel rule:

he has to clear everything alone.

No teammates. No backup. No second chances.

Every floor is a deadly game. Every quest, a gamble with his life.

But what begins as desperation soon turns into something else.

Through relentless training, repeated failures, and sheer obsession,
Jin-hyeok begins to grow—stronger, sharper… and far more dangerous.

Along the way, he forms unlikely bonds with NPCs, demons, and even celestial beings,
protects a mysterious child prodigy, and uncovers secrets buried deep within the Tower.

Yet the higher he climbs, the more he realizes—

this Tower isn’t just a test.

It’s a battlefield of gods, clones, and cosmic horrors.

And he?

He’s the only player forced to face it all solo.