Cultivating Immortality Across Two Worlds: Who Installed the System Backward?

[The golden finger was installed backward, but I'm invincible]

Du Zhe travels between two worlds: one is a path to immortal cultivation and longevity, the other a doomsday world crawling with a hundred ghosts.

Unfortunately, his aptitude is dull. He has spent a century in the cultivation world and is still at the Qi Refining stage, while in the doomsday world, an invisible barrier traps him inside a residential complex.

On his 120th birthday, the System finally finishes loading... but, System, why did you install it backward?

The [Karma-Slaying Cultivation System] was installed in the doomsday world;

The [Doomsday Survival System] loaded into the cultivation world.

Just as despair sets in, Du Zhe realizes: Wait, something's not right. It seems... the backward-installed Systems can still work!

Doomsday Survival System: [You have survived in the doomsday world for 43,800 days. Reward: Max-level skill, "Insight"!]

Karma-Slaying Cultivation System: [You have slain 1,000 Corpse Demons. Reward: The cultivation method, Earth Fiend Savage Body Art!]

Huh? I can claim doomsday survival rewards by meditating in the cultivation world? Do the zombies roaming everywhere in the doomsday world count as Corpse Demons?

If that's how you want to put it, System, then I get it:

Abusing bugs ×

Making reasonable use of the mechanics √

In the cultivation world, where everyone pushes themselves to the limit, Du Zhe can get stronger by running his daily quests, leaving the greatest prodigies so furious they question their existence.

In the doomsday world, faced with the ghostly rules and bizarre tales that have brought so many survivors to ruin, Du Zhe says: "What gibberish are you spouting? Take this Solar Sword Art!"

Years later, when Du Zhe has become the strongest in both worlds, he finally discovers: What? So the Systems weren't installed backward after all...