With a little effort, you could easily creep up on opponents with a combination of Wishiwashi and Wishiwashi ex
This means there are hundreds of thousands of individual serialized cards out there, although some have smaller runs than others
You can also explore accessories like the dynamic tuck box to house your cards in style, or use custom dice and game mats to replicate the full TCG experience
I made a 3D Pokmon card I kept seeing TikToks about people making 3D Pokmon cards out of their duplicates, & they were all so beautiful
When people have more disposable income, they're more likely to invest in hobbies, which can drive card prices up
You can also use monsters your opponent controls to complete an Extra Link - if your opponent has 3 co-linked monsters in a row in their Main Monster Zones, summoning 2 Links to the Extra Monster Zones co-linked to those 3 will allow you to complete the Extra Link