MMORPG: The Elementalist - Chapter 21

Betrayed and left for dead, Richard Blackwood—formerly known as the world renowned hero Astralis—awakens a decade later to find the world has moved on, and an imposter now wears his mantle. Disguised as a rookie in the Mage Guild, he quietly hunts for answers.'If my little sister is levelled above me, then what about everyone else? How much stronger have the bastards who betrayed me grown while I was dead?'Richard must grow stronger once again, and rise much higher than the S-Rank.'What the fuck? I almost die, and I get a power up?'Not harem.

I transmigrated into the gacha game I abandoned for 10 years.But, the state of the heroes I raised is strange.

Luo Qing Chen is a wandering spirit that died thirty thousand years ago, roaming the Chaos Space

In order to not turn into dust, she is bound by an ice cold system to travel through time and space to complete missions.

Girls that pretend to be weak?  Slap them without explaining.

A silly cannon fodder?  Helping them amass treasures.

Meeting a real male god?  All of them will pamper.

System: Dear masters, what do I do if my host even dares bully the heavens?  Waiting for an answer, it’s urgent!

A certain male god: Change systems.

System: ヽ〔?Д?〕丿

- Description from Novelupdates

A story about a traveler who crossed into a parallel universe, relying on his Proficiency ability to continuously grind experience and become stronger.