Naruto: Paws and Whiskers - Chapter 125

This is a world with only oceans, through which scattered are countless small islands and treasures.With swords, gunpowder, sailing ships, and most important, the Treasure Hunting System, Alka is ready to dominate the oceans!「Map detected」「Scanning for Treasure」「Scan complete」「Happy Treasure hunting!」

Kael was once a being so powerful even the gods feared him—until he was thrown into The Null, a realm of endless torment and eventually cast into inexistence. But he returns, reincarnated as a powerless beggar in a broken world ruled by monsters and corruption.With memory of godly blood on his hands, he is determined to reclaim his strength, survive the Nexus's deadly trials, and tear down the heavens themselves.But it's a matter of time before the gods and celestials know he’s returned. And this time, they will not make the same mistake twice.> ◇ Ravager (Rank E) Eliminated. 20 VRP Gained.> ◇ 0.00109% Memory Unlocked. Forgotten Technique: Blight Shield Relearned.> ◇ Ather'valis, The God-Killing Blade, has been acquired.

Huang Dan’s pain nerve is innately different from the ordinary people. A little tore in his skin can cause him to sweat all over his body painfully to the point of him unable to make a word out.

Somehow, he began to cross world, following Mr. System to do the tasks…

In the first world, Huang Dan realizes what it means to die painfully and to live to die again.

TL’s summary:
MC suddenly transmigrated and is bind to a system, requiring him to solve mysteries. Born with a higher degree of pain sensitivity, he met different people in the different worlds and learns what kind of emotion smiling is.

- Description from Novelupdates

Yuseong, a genius doctor who made a name for himself in the medical community, considered the operating room his home. One day, he died in a traffic accident, and when he regained consciousness, he found himself in another world.But… Saint… Holy Kingdom… Healing magic?“I worked so hard to learn medicine, and now you’re telling me I can just touch someone and they’re healed? Oh, I’m going to lose my mind.”