The characters Ruddin, Hathy, Clover, Lancer, and King all took their designs from a series of playing card illustrations that Tumblr user Kantonytes published in 2012, the year Deltarune first started development. In a tweet posted shortly after Chapter 1's release, Toby Fox credited Kantonytes' work as a key inspiration for the game as a whole.
Contributed by game4brains
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