First, think about the characteristics of the cards you want to cross over. If it's a monster card, consider the stats, type, and abilities. For example, if you're crossing a Winged Beast from the original series with a Machine - type from GX, you might give it the ability to fly like a Winged Beast but also have some mechanical enhancements. Second, look at the lore of both cards or series. You can base the new card's backstory on that. For instance, if a card has a story about an ancient power in one series, combine it with a similar concept from another series.
The number of graphic novels is impossible to pin down precisely. It's a constantly evolving field with countless titles published each year. Different sources might offer varying estimates, but it's safe to say there are a huge amount.
The number of novel mutations is difficult to determine precisely. It depends on various factors like the scope of research, the organisms or systems being studied, and the methods used for detection.
It's really hard to say exactly how many English novels there are. The range is huge, from modern bestsellers to centuries-old masterpieces. It's an ever-expanding collection that defies an exact tally.