Harry Potter: Eclipse. - Chapter 48:

Silas Blackwood wakes up with a machine in his chest – his missing mother's parting gift to help him survive the war with the Fae. This “system” grants him bizarre abilities: neuromancy (magic of the mind), biomancy (magic of the body), and essomancy (magic of souls and essences). Oh, and it fused a leviathan's mana core into his body. Because why not become part sea monster?At Arcanium University, a military boot camp churning out mage knights, Silas finds himself targeted by rich brats who think being born with a silver wand up their ass makes them special. When they leave him for dead, Silas decides it's time to show these spoiled kids what real power looks like.As Silas grows stronger, he discovers he can upgrade himself by absorbing essences from magical beasts and demons. Just when he thinks he's got a handle on things, Silas learns his mother's alive, and now he's got a new mission: a rescue that'll take him and his friends straight into the depths of Hell.

Yang Feng somehow transmigrated into a different world and received a legacy of an ‘ancient high tech’ family, which does not directly raise his power, but gives him the technology to build things which are way more advanced than the seemingly medieval world.

But to build something you need resources and energy. To receive resources you need strength. To gain strength you need knowledge. To gain knowledge you… need strength? or a background? Or maybe a fully armed army of high tech robots who aren’t afraid of death?

But is this legacy really for him to keep?

- Description from Novelupdates

There’s SIS in great Britain, CIA in the US. In Huaxia, there’s Dragon Division, known as the mysterious power of the East.

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates