Tensei Shitara Slime Datta Ken (WN) - Chapter 399

“Blake traveled across parallel worlds and arrived at the Cretaceous Period! What’s more, he became a Tyrannosaurus rex! Fortunately, he obtained the Evolution Template system!

[Ding! Super Tyrannosaurus template unlocking progress: 100%] Blake transformed into a Super Tyrannosaurus!

[Ding! The King of Monsters template is now unlocked!]

Just when it was unlocked to 25%, humans from the future arrived at the Cretaceous Period through a wormhole! Facing the prehistoric behemoth, all researchers were shocked!

“Oh! My! God! I can’t believe my eyes!”

“A monster! It’s a monster! I knew it! I knew that the shows I watched when I was a kid aren’t cartoons! They are documentaries!”

“How can it look so much like Godzilla? Oh my goodness! Could it really be Godzilla?!” Blake looked at the tiny researchers in front of him, then pointed his finger at his belly and giant abyssal mouth. What are you looking at? I am a little hungry!”

A data loving young man from Earth has an accident which transports him to a dark land filled with terrifying creatures and magical powers. Fortunately for him, he has a Biological Assistance Chip to ease his path. However, things in this bizarre and strange world are not always as they seem, and, though it is a tremendous asset, the chip doesn’t always work as expected. With all of the crazy creatures and magical mayhem around him, one can only wonder what the future holds for this young man…

- Description from novelupdates

After experiencing heartbreak from being abandoned, he enlisted in the military.

And then, he became a war hero.