The antonyms for the term "art cards" would likely include words such as plain, unadorned, and unembellished. These are words that connote simplicity and lack of decoration or artistic value. Other possible antonyms might include words like generic, mundane, or unremarkable - all of which suggest that the item in question lacks any distinctive or unique features. Ultimately, whether or not something qualifies as an antonym for "art cards" depends on the specific context and the intended meaning of the term. However, anyone looking for a contrast to the creativity and beauty of art cards might consider exploring these alternative descriptors.