DxD: Matsuda? - Chapter 42: Akeno’s Love?

I reincarnated as a lizard in a martial arts world.“Roar!”“He’s using the lion’s roar!”“To deflect the Ten-Star Power Plum Blossom Sword Technique! Truly indestructible as they say!”“This is… the Heavenly Demon Overlord Technique! It’s a Heavenly Demon, the Heavenly Demon has appeared!”It seems they’re mistaking me for something else.

With the Legendary Mechanic System, I transmigrated to Marvel Universe to be Dr. Zola’s assistant.

With Mechanical Force Analysis, I can learn every black technology.

Winter Soldier’s arm? I built a better one for you.

Iron Man’s armor? I already made it a decade earlier.

Doc Ock’s tentacles? I am the one who provided core technology.

Hulk’s mutation? Sorry, I was there and got hit by the radiation too.

As for a certain purple potato, can he collect all Infinity Stones?

……

However, I only had one simple ultimate dream. That is to go home…

- Description from Novelupdates

At 79, Adom is an old mage who has known nothing but illness and regret. When the world finally burns and all hope turns to ash, at the last beat of his fading heart, a mysterious being appears in the dimming light with a simple question:“If you could try again, would you?”What's left to lose when you've already lost everything?A handshake seals the deal, and Adom wakes up on his old school grounds, sixty-seven years in the past. When everything is still possible. A second chance with all his knowledge intact, his memories preserved, and his youth restored.This time, Adom wants it all: to feast on food he's never had, to travel a world still full of wonder, to finally live the life he dreamed of. There's just, as always, one small catch—he needs to prevent the end of the world first.But as Adom will soon discover, changing history might demand sacrifices even greater than watching it burn...

In a modern world where cultivators need a place to cultivate or vent their boredom, there are private businesses that set up instance dungeons with the aid of technology and cultivation magic to enable cultivators to train and commoners to experience the life of cultivation. They are called dungeon suppliers.
Xie Jin's one and only dream was to be a dungeon supplier and when his only relative passed away, the relative's inheritance gave him a plot of land and surprisingly, a 'System' Module which the relative had previously used.
With the help of the system, Xie Jin decided to pursue his dream of becoming the number one dungeon supplier.