MTL - Girl, I’ll Teach You Cultivation - Chapter 133 stone

You thought being reincarnated as an extra-side character was bad? Imagine being thrown into the body of a villain who is disowned by his own family and discarded by the author.

Wang Xuan entered Longmao Square and was trapped in it. When he finally left, it turned out…

This is the last building on earth.

- Description from novelbuddy

When a person dies, they either die light as a feather (aka unimportant) or heavy as Mt. Tai (aka very important).

Kuramoto Daisuke, a freshman in High School was suddenly exposed to someone vanishing in front of him. Turns out he was admitted to a Special Class full of Isekai Heroes that were regularly summoned to Otherworlds since the start of their Middle School. He was told that he was to become their Support to prevent each of the Heroes' fate of dying in the world they were summoned into. Though mediocre, he realized that his ability has a great potential but it needs a lot of hard work on his part.

Unconvinced of being just the Support Character, he vowed to excavate his mediocre ability, all the while supporting the Heroes using it.

And maybe more.