There are only two ways to label a card with a demon mark.
First, of course, is to use a demon card + another card.
He sits comfortably on the sofa, resting his neck directly on the top of the sofa's backrest and closing his eyes.
"Begin."
He sets up batch previews, and starts the process.
Whoosh, whoosh, whoosh!
Preview results burst through his mind one after another.
The Cube Card System panel even thoughtfully provides him with a progress bar, showing the results of batch processing.
But Ree Shil can't see it because his attention is entirely focused on the strong dizziness he's feeling.
After a while, the combinations are finished.
He leans his neck back and squints for another 5 minutes, waiting for the dizziness to completely fade before finally opening his eyes again.
"Uh, the things previewed are much less than I imagined."
Looking at the results in his mind, there is very little fusion success between the new batch of demon cards.