The most valuable cards from the Obsidian Flames set typically include holographic rare cards, first edition prints, and cards featuring popular Pokemon
There are also a bunch of other designs for double-faced cards in the set, including sidequests, characters that transform into their summons (so they have saga creatures on their back face), and even a pair of characters that can meld together
I'll probably implement that in a few other places eventually
The best part is that you can sell Yugioh cards for cash easily at such stores, though at lower prices
I would much rather try and get my value in tempo positive ways or in bigger chunks later down the line
In exchange, you get to search your library for a Dinosaur creature and put it directly onto the battlefield