And so the 18th Legion went to fight there (gate jieitai kano x Warhammer 40K)

"In the grim darkness of the distant future, there is only war."
In a corner of the multiverse where magic and gunpowder compete for the right to decide who kills faster, the Empire Saderan wages its final war against the last warriors of the Rabbit Kingdom. The spears are ready, the arrows drawn, and Queen Tyuule watches from her hill as the weight of history tips against her people.
She is ready to die...
or to drag the Empire down with her.

But fate rarely obeys the plans of kings.

On the eve of the massacre, an impossible phenomenon breaks the logic of the world: a Gate materializes in the middle of the battlefield, a huge arch carved from ancient stone, as if someone had torn it from an empire that died millennia ago and hung it in the air.
No demons or gods emerge from that Gate.
Men emerge. Soldiers. With armor reminiscent of extinct civilizations and a language that none of those present can understand. They do not come to make a pact. They do not come to negotiate.

They come to kill.

And to take slaves.

But they do not know who protects this world, the salamanders, and their fury will not be long in coming.