The hardest part about reading Yu-Gi-Oh! cards is the text box contains both game rules set, summoning text, and finally rules text. They aren't always listed in that order on the card. This game is OLD. Here's an attempt at re-templating Yu-Gi-Oh! cards in an attempt to make them more readable. This assumes some game rules are removed from the card and added to the game system.
Jinzo Example
Summoning Requirement Box: This card has a summoning
requirement and they are listed in a box above the text box. This
removes ambiguity between a cards cost and effect. Currently the game
uses a ';' notation. It's clear but breaking it up two two paragraphs is
easier to read.
Keywords: There are many
effects that could be Keywords in the game to save reading time. Konami
once argued that Keywords made that game more difficult for newcomers to
understand. I understand that perspective in general but cards are
simply to difficult to read quickly now. Condensing information make it
easier to learn and build on top of.
Spirit Reaper Example
Multi Keywords: Here's one with more then one Keyword. Some cards might still be lists but it's easy to identify the game effect now.
Timing Clauses:
I used the sword symbol here as a marker of when this effect triggers.
In this case, when it attacks. Modifying effects come after the effect
timing symbol. This will help clear both timing questions and
interaction timing questions.
Bigger Art Frame: The levels overlapping with the frame and moving the monster type to the top right corner open up more room for the artwork!
Future Proofing
These concepts may seem minor at first but they are going to make more players able to discover the game experience you created. Make it easy for them to get through the rules! You want to make your game as easy to play as possible with respect to the audience it's designed for.
In addition to usability and accessibility, it also helps massively with future proofing your game. As games get older, cards are going to get more complicated. With the right system in place, you can prevent your cards looking like the one below.