Aside from my passion for the Sengoku period, I chose Sekigahara partly due to an exhibition I visited in Kyoto a couple years ago. The purpose of that exhibition was to commemorate the 400th anniversary of Tokugawa Ieyasu's death, focusing specifically on the Battle of Sekigahra. Many national treasures from scrolls to armors were on display in the Museum of Kyoto during the summer of 2015. I happen to own a museum catalog of most if not all of the objects that were featured during that exhibition. Thanks to this catalog I was able to revisit it and introduce a few of the displayed objects to my viewers.
I was mainly inspired by two games I have played or am familiar with. One of them is a Chinese card game named Sanguosha (Legends of Three Kingdoms), which is based on a combination of a historical period in 14th century and a novel written about that period. Though I was not invested in this game myself, I remembered it fondly as a popular childhood card game. The second game I was inspired by was Slay the Spire, a highly praised card game available on many platforms. I definitely had this game in mind when I was brainstorming ideas.
I used a website called Dulst. Having no background in programming or coding at all, I was able to create a game that fits my need. It provides 70% of the foundation of a card game, including UI element and AI setup. Without this website, it is impossible for me to create anything in a limited time period.
Even though Dulst had provided me with an abundant of information, I had a difficult time figuring out how to input complicated commands for a card. Unfortunately, I had to opt for a series of much more simplified commands due to my limited or actually nonexistent coding skills.
The main software I used to draw some of the card designs is Pixel Studio. It fulfills all of my requirements. For example, it allows me to easily trace the outline of an object on my device. As someone who is not skilled in visual art at all, I was able to create something that I think somewhat resembles the real object.
The only two websites I used to obtain the images aside from the ones I drew are Wikipedia and a free-to-use Japanese site (Irasutoya).
I used genial.ly. It is a fun and easy-to-use site. It allows me to add all kinds of animations and visual effects.