From A Stronghold NPC To The Final BOSS - Chapter 544 - : 543 he has a secret

It’s the vacation of a lifetime, a trip to a remote island filled with geniuses and murder.

​The world, Earth, was devastated by the Great Incursion, an apocalyptic invasion by dimension-hopping monsters. Humanity's only hope now lies in Galaxy Fall, a newly accessible parallel world where they can gain strength through a System of quests and missions.​Five hours after the Invasion, the betrayed survivor Mirabella is mysteriously reborn and gains a unique power: the [Master Account System].Her initial skill is the deceptively simple but devastating 'Multiplier x100', which applies a 100 times buff to all her offensive capabilities, including physical attacks, spirit energy skills, and damage-over-time effects.​Mirabella must now transform from a silent survivor into the world's most feared warrior, who was only scared of one thing, which is?“I Hope I don't run out of opponents in Both worlds.”

The first time they met they had battled fiercely, just for a mere bunch of herbs. She needed it to save people, and he wanted to use it to save his own life.

“Let go of it, or you will die.” The man’s violet eyes were cold and sinister as he said in a low voice.

She held on tightly to the base of the herb and pulled its roots right out of the ground, before she turned her eyes back with a crafty smile. “It’s mine now. Snatch it from me if you can.”

When they met several years later they were no longer on opposing sides in hostility. In order to repay the debt for having stolen the herb back then, she went on to miraculously cure his body’s condition, relieving him of the inhumane torment that wrecked at his body day and night. He was amazed by the godly skills in Medicine she possessed and his heart went on to fall irrecoverably head over heels in love.

- Description from novelupdates

Awakening to a post-apocalyptic world infested with zombies and mutated monsters, Alex makes a startling discovery: he possesses a system that grants him access to unlimited resources every day.【Congratulations, you've received unlimited bottled water.】【Congratulations, you've received unlimited 9mm bullets.】【Congratulations, you've received unlimited cold medicine.】...With each system notification, Alex's chances of survival soar while others struggle to stay alive.As everyone else fights for their lives, Alex finds himself living in luxury, residing in a lavish mansion where he leisurely sips red wine and savors grilled delicacies amidst the chaos of the end times...